1 10. If 23x of x? (A) = 8, then what is the value ~ 1 (C) 1- (B) 1 3 3 (D) 2 11. If 33x = 27 2x value of x? (A) -1 (B) then what is the ~ 12. If 323 =3 k X value of k? (A) 2 1, 3 3k - (B) 9 (C) 1 3, (C) (D) 2 (E) 3 then what is the 10 (D) 13 (E) 20 13. If ab = 3 and ab 2 = 18, then what is the value of a? (A) ~ (B) 1 2 (C) 2 (D) 6 (E) 54 14. If x 2 = 25, then x 3 = (A) -125 only (B) 125 only -125 or 125 (E) 15,625 (D) 15 (C) 15. If 5y 2 = 25, then what is the value of 5y 4? (A) 125 (B) 525 (D) 3,125 (E) 15,625 (C) 625 16. If y2k = 36 when y and k are positive integers, then what is the value of y3k? (A) V6 (D) 108 (B) 6V6 (C) 54 (E) 216 17.1f3 x = 10 , then 3- 3x = (A) -1,000 ~oo (D) 1 , (B) -27 (E)~ 20 1 (C) 1,000 18. If yr x 4 y 2r = 32, then what is the value ofyT? (A)~ (B) 2 (D) 4 (E) 8 (C) VB 19. If 2n = 32, then what is the value of sn-2? (B) 25 (E) 3,125 (A) 5 (D) 625 20. If 5x = (A) 4 125, then 4 3x (B) 8 5 (C) 16 (C) 125 = (D) 64 (E) 256 21. If IOn = 1, then 10 2n+ 2 = (A) 1 (D) 1,000 (B) 10 (E) 10,000 (C) 100 22. If x 7 = a and x 5 = 3m, which of the following represents m? (A) 1-2 x (D) _1_ 3x2 (B)~ x2 2 (E)~ 3a 23. If c = a 2 b3 and b = a 2d 4 , which of the following is the correct expression for c in terms of a and d? (B) a 7 d 7 (C) a 7d 12 (E) a 8d 12 24. If yn = x 3n , where n, x, and yare posi tive integers, then what is x in terms ofy? (A) 0 (D) 3y (B) vY (C) 2:: 3 (E) y3 25. If a 4 = x and b3 = y, then what does (ab )12 equal in terms of x and y? (B) x 3y 4 (E) x 12 y 12 pI. ----------------------_J • An equation is a statement of equality between two expressions. The solution to an equation is a value of the variable (a letter used to represent a number) that makes the equation true. To find the solution, work to get the variable on one side of the equation and a number on the other side of the equation. Remember, to maintain the balance of an equation, you must perform the same operation on both sides. SKILL SET Match the equation in Column I with its solution in Column II. Column I 1. 2x-9=-11 A 3 2. -x + 100 = 25 B. x 3. 7(x - 3) = 3x - 17 C. x = 100 2 + 1 = -x 1 - 9 4. -x D. x 4 • Column II 5 2 x=l =-1 = -100 Solve for x. 5. 6x + 12 = 4 x 6. -=7 5 8. 3(x + 8) = 2x + 19 9. 2,800 = 14 lOx 7. 5x + 12 = x + 8 2 10. -x 3 4 + 6 = -x +4 5 Match the equation in Column I with the equivalent equation in Column II. Column I Column II 1 11. -x +5=1 2 A 12. - 2(5 - x) = 9 B. x + 10 = 2 13. 6x + 15 = 3 C. 2x - 10 = 9 2x+5=1 • (lZ) SAT-Type Problems 1. If 3(5)(11)y == 11(3)( -15), then y (A) -660 (B) -3 (D) 330 (E) 660 (C) 3 2. If -2(5)(6)r = 5(6)(7), then r (A) -9 (B) -7 -~ (D) = (C) = -'i 2 (E) 5 7 3. If 2(5)( -7)m (A) -40 = 5( -7)(8), then m = (B) -4 (E) 44 (D) 40 (C) 4 2 4. Given that ~ = p, what is the value of 12p? 4 2 2 (A)~ (B)~ 12 3 (D) 4n 2 2 5. If -x = 4p, what is the value of 12p? 6 2 2 (A)~ (B)~ ·32 (D) 2x 2 6. If ~ 3 (E) 3x 2 = 15, then 3x = (A) 5 (B) 12 (D) 45 (E) 135 7. If 254 1,000y (C)x 2 = (C) 18 40, then y = (A) 0.00635 (B) 0.0635 (D) 6.35 (E) 63.5 (C) 0.635 8. If 5,432 = 50 then k = lOOk ' (A) 0.10864 (B) 1.0864 (C) 10.864 (D) 108.64 (E) 1,086.4 9. If (x + 5)(8 - 5) (A) 5 ~o. (B) 10 60, then x = (C) 15 If (r + 6)(9 - 3) = (D) 20 18, then r = (E) 25 = (A)-9 (B)-3 (C)O (D)3 (E)9 11. If 6(x + 2) - 3x = 8, then x = (A) -~ (B) -± (C) -~ 333 (D) ±3 (E) 12. If 5x - (x - 2) (A) 2 (B) 3 13. If 4x - 4 (A) 4 (A) 3 18, then x (C) 4 (D) 5 = (E) 6 = 14, then x + I = 2 (B) 5 14. If 3x + 1 = ~ = (D) 18 (C) 7 2 5, then x + - 3 ± (B) 2 3 (E) (D) 3 (E) 22 = (C) 2 3 1Q 3 15. If 7 - 5m = -23, then m -I = 5 (A) 3 (B) 3 (C) 5 5 I 5 (E) 6 I (D) 5± 5 16. If 3x + 15 1 5 = 33, (B) (D) 18 17. If3(2x + 4y) then x + 5 lOl 3 = (C) 11 (E) 30 = R, then 3(4x + 8y) 3R (A) 2R (B) (D) 6R (E) 9R (C) 4R = '------------ ax + b = ex - d is an equation with several variables. You can solve for anyone of the variables by following the procedures covered in the previous section. SAT-Type Problems 1. If a + b (A)O 2. If ab = a - b, then b (B)l (C)a = (O)-a (E)-2a ~, then b = = (A) -1 only (B) 1 only (C) -lor 1 (E) -a or a (0) 0 3. If r = pq, which of the following must be equivalent to rp? (A)pq (0) pr 2 4. If k = am, which of the following must be equivalent to m 2? (A) If; (0) k (B) ! a (C) kam 2 a 5. If x = Y, z which of the following must be equal to yz? (A) xz (B) xy (0) xz 2 (E) xyz (C) xy2 (/J9) 6. If a 3 + b 3 b equal? =: a 3 + y3, then what does (B) y3 + 2a 3 (D)y3 + a 3 ) y3 .,» y3 2a3 - (E) y 7. If 3a = 12C!'., then what does c equal? 4b c (C) 4b (A) 4 (B) 16 (D) 16b (E) 48ab 4abc th w h a t IS . 8 . If - -- 4abcd ,en 5xyz m the value of m? (A) 5dxyz (B) d (D) 5xy (E) 5abc (C) 5abcd 9. Which expression represents x if a =: (A) -~ b (B)_b_ (C)-~ a-c a (D) a - c a+c +c (E) a b b 10. Ifa(b + 1) (A) "* O? !!.... - c and if x x !- - =: then b C, = 1 (B) 1 1 (E) c - a - I C - a (D) C - a a +a+a 11. I f - 3 and c (A) 12. If 1 4 c+c+c+c =: 4' "* 0, then (B) 1 a =: C (C) ± 3 (D) 2 a +a +a _ b+b _ 3 - -2- - and c "* 0, then -ab C + (D) ± (E) 8 C + 4 C +c =: C (A) ~ 4 (B) 1 (C) b 6 (E) l b 13. The ratio of p: q is 3: 5 and the ratio of q: r is 4: 9. What is the ratio of p: r? (A) 1- (B) 1- (D) 1- (E) ~ 3 2 (C) 4 ~ 15 9 14. If the ratio of a: b is 2: 5, and the ratio of d: b is 3: 2, then what is the ratio of a:d? (A)~ (B) -.£ (E) ~ 25 (D) ~ 3 (C)~ 5 15 2 15. The ratio of a: b is 2: 5, the ratio of c: d is 5: 2, and the ratio of d: b is 3: 2. What is the ratio of a: c? (A) ~ (B) 75 ~ (C) 25 1- (D) 2 ~ 5 (E) Value cannot be determined from the information given . If a + b = c + d b + c equals (A) 22 (B) 44 = -a - d (C) 66 = 22, (D) 88 (E) Value cannot be determined from the information given. * 17. Ifz 0 and 2x = 3y = 4z, what is the value of x + y in terms of z? (A) ~z (B)!z (C) 2z (D) 1Q.z 3 3 3 (E) Value cannot be determined from the information given. 18. If P = 2l + 2w, then l= (A) P - w (B) P - 2w 2 (D) P + 2w = 2 p + prt, thenp = (A) A rt (B) (D) rt (E) rtA A +w (E) 2P - w 2 ..... !fA (C)P A 1 + rt (C)~ 2rt '------------------ To solve a set of equations with two variables, first eliminate one variable. The method you use to eliminate a variable depends on the equations. x + y = 15 y = 2x (1) (2) Substitution Since y = 2x, substitute 2x for y in equation (1). x x + Y = 15 + 2x = 15 3x = 15 (1) x=5 Substitute 5 for x in equation (2), and solve for y. y = 2x (2) y = 2(5) y = 10 Addition x + y = 10 x - y =4 (1) (2) x + Y = 10 x - y = 4 Adding the two equations will eliminate one of the variables. 2x = 14 x=7 Substitute 7 for x in either equation, and solve for y x + Y = 10 (1) 7 + Y = 10 y=3 Subtraction x x + y = 9 (1) + 2y = 11 (2) x + y = 9 - x - 2y = -11 - y = - 2 Subtracting the two equations will eliminate one of the variables. y=2 Substitute 2 for y in either equation and solve for x. x + Y = 9 (1) x+2=9 x=7 SKILL SET Solve for x and y. 1. x +y = y = 28 3x 4.2x + 2y = 16 x = 3y 2. x + y = 32 3. + Y = 15 x + 2y = 23 6. x 3x x-y=8 5. x + 2y = 11 3x 2y = 1 x +Y = 9 + Y = 19 SAT-Type Problems 1. If x 3b and y = = 3. If x + Y - z then x = 2 , what is y 6b + 4 = 8 and x .- y + z = 12, in terms of x? (A) _2_ (B) _1_ x+4 x+2 (D) x 2. Ifx 2 + 2 - 7 =y and x (A) 8 (D) 14,228 (E) 2x + (A)2 (B)4 (C)10 (D)20 (E) Cannot be determined from the information given (C) 2x 4 4. Ifx + 7 = 2y andy the value of y? = 4, then y 2 (B) 80 (E) 14,329 - 1 = (A)-5 (B)3 = 2x - 1, what is (C)5 (D)9 (E)13 (C) 81 5. If 2x + y = 6 and x - 6 = y, what is the value of x? (A) 0 (B) 2 6. If 5x - 2y (A)1 (C) 3 = 10 (B)4 (D) 4 (E) 6 = ~, then y = and x (C)5 (D)7 (E)9 = ~ and m - a = 80, then what 7 . If ~ 5 m is the value of m? (A) 2 (B) 20 (D) 120 (E) 200 (C) 80 8. If 3m + 2n = 16 and m - 2n what is the value of m? (A) 4 (B) 6 (C) 8 (D) 10 9. If x + y = 4 and x - y does x equal? (A) k +4 (B) 4k (D) 2 + 1- k 2 (E) 2 = = 0, then (E) 12 k, then what (C) 4 -1- k 2 k r + t = sand r - t = -s 10. Based on the equations above, which of the following must be equal to t? 15. If5x - 4y = 22 and 3x + 6y = 30, what is the value of x - 5y? (A) -8 (A) r:s (B) -r (D) r (C) 0 (E) s (A)6 y -z =x 11. Based on the equations above, which of the following must be equal to z? (B) x (D) -x (C) y (E)-y (C) -2 (D) 0 (E) 2 16. If 2x - y = 0 and x - 2y = 3, then 6x - 6y x+y=z (A) 0 (B) -4 = (B)12 (C)18 (D)21 (E)24 17.1f9x + 2y 2 - 3z 2 = 132 and 9y - 2y 2 + 3z 2 = 12, then x + y = (A) 3 (B) 8 (C) 16 (D) 120 (E) 144 18. If a, b, and c are positive integers and if a = 2b, and a 2 + b 2 = c, which of the . following cannot equal c? 10 11 x y +12 32 (A) 5 (B) 20 (D) 125 (E) 500 (C) 50 9 8 x z +7 37 12. In the correctly worked addition prob lems above, what is the value of z -y? (A) -14 (B) -12 (D) 12 (E) 14 13. If x + y = 12 and x - y the value of x 2 + y2? (A) 20 (B) 24 (D) 104 (E) 208 (C) 5 8, what is = (C) 100 14. If8x - 4y = 20 and 4x - 8y is the value of x - y? (A) 1 (B) 2 (C) 3 (D) 4 = 4, what (E) 6 I~ J l. The absolute value of a number is its distance from zero. Symbolically, the absolute .Jue of x is written as Ix I. Thus, 131 = 1-31 = 3. Both 3 and -3 are 3 units from zero on the number line. When you solve absolute value equations, you will consider two possibilities: 1. The expression inside the absolute value sign is positive. 2. The expression inside the absolute value sign is negative. Each equation has possible solutions for both cases: Example Solve Ix + Case 1: 51 = 12 x + 5 is positive. The expression is therefore equal to 12. Simply drop the absolute value sign and solve. x + 5 = 12 x=7 Case 2: x + 5 is negative. The negative of the expression is now equal to 12. Exchange the absolute value sign for a parenthesis preceded by a nega tive sign. -(x + 5) = 12 x + 5 = -12 x = -17 Answer: x = 7 or x = -17 SKILL SET l.What is the sum of the solutions to the equation 1-5x - 51 = 45 (A) -18 (B) -9 (C) -2 (D) 2 (E) 18 2. -12 and 24 are solutions to the which of the following equations? (A) (C) (E) I-x - 61 = 18 Ix + 61 = 6 Ix - 61 = 18 (B) (D) I-x + 61 = 30 Ix + 61 = 30 3. What is the product of the solutions to the equation (A) -30 (B) 24 C) 30 (D) 48 ~ + 6 = 4? (E) 180 (~ 4. What is the smaller solution to the equation 18 - ~ (A) 10 (B) 14 (C) 22 (D) 56 = 4 (E) 88 5. At Family Math Day, first-grade students won a prize for guessing within 8 the number of marbles in the jar. If the jar contained 44 marbles, how many winning numbers are a multiple of 3? (A) 2 (B) 3 (C) 4 (D) 6 (E) 14 6. What is the larger solution to the equation /6 (A) 17 (B) 30 (C) 60 (D) 72 ~ I~ 11? (E) 102 7. What is the difference between the solutions to the equation (B) 10 (A) 7 (C) 12 (D) 18 SAT-Type Problems 1. What is the product of the solutions of the equation 13x + 211 = 9? (A) -49 (B) -40 (D) 40 (E) 49 (C) -9 2. -6 and 14 are solutions to which of the following equations? (C) Ix + 41 Ix - 21 (E) Ix (A) 10 (B) = 12 (D) = - 161 = Ix - 41 = 10 Ix + 161 = 10 10 3. Which is the greater solution for the equation I -3x - 121 = 30? (A) 6 4. If x (B) 10 (C) 14 = -2, what is (D) 15 the value of IxO I - Ixl I + Ix 2 1 (A) -6 (B) -5 (D) 14 (E) 15 Ixsl ? (C) -3 (E) 18 (E) 30 12 + ~ I= 5? 5. x = 3 is the complete solution set to which of the following equations? (A) x - 6 = 9 ,J) (E) (B) -2x = -6 I-x + 31 Ix I = 3 = 6 (D) 14x - 61 = 6 6. If Jorge scores within 3 points of Sam, they will be placed on opposing teams. Sam scores 12 points and they play on opposing teams. How many different point totals could Jorge score? (A) 9 (B) 8 (D) 6 (E) 3 (C) 7 7. Prizes are awarded to all participants in a charity event who guess within 5 the number of people attending the event. If 43 people attended the event, how many guesses are a multiple of 3? (A) 5 (B) 4 (D) 2 (E) 1 (C) 3 :~t What is the sum of the solutions to ...•. the equation I -3x + 181 = 6? (A) 4 (B) 8 (D) 16 (E) 20 (C) 12 : 9.4 and 8 are solutions to which of the following equations? Ix + 21 (C) Ix + 61 (E) Ix - 61 (A) 6 (B) = 10 (D) = Ix - 2/ = 2 Ix + 161 = 10 = 2 10."-- ich is the smaller solution for the equation 116 - 4x I = 8? (A) -6 (D) 2 . (B)-4 (E) 4 (C) -2 Part 2: Equations < < •• , <;1. What is t~e sum of the solutions to .... the equatIOn 1-3x + 181 = 6? (A) 4 (B) 8 (D) 16 (E) 20 175 10. Which is the smaller solution for the equation 116 - 4x I = 8? (C) 12 (A) -6 (B) -4 (D) 2 (E) 4 (C) -2 9. 4 and 8 are solutions to which of the following equations? ."( (A) Ix + 21 (C) Ix+61 =10 (E) Ix - 61 =6 (B) Ix - 21 = 2 (D) Ix + 161 = 10 = 2 '---------------------- Binomials are algebraic expressions with two terms. +y 3x x 2 - y2 4a 2b - 1 You can use the distributive property or FOIL to multiply binomials. • Using the distributive property, multiply each term of one binomial by each term of the other. (x + 5)(x + 3) = x(x + 3) + 5(x + 3) = x2 + 3x + 5x + 15 x 2 + 8x + 15 = • Using FOIL, First L st rr=ri + + (x 5)(x u t 3) = x 2 t + F ~ 3x + + 15 I L 5x a Outer = x 2 + 8x + 15 The product x 2 + 8x + 15 is a quadratic expression. A quadratic expression is an expression of the second degree. You can factor a number or a quadratic expression by breaking it up into its factors. < 12 '---y---' = 3 X 4 '----v--' product factors x2 + 2x = x(x + 2) '----r--' '--r-' product factors x 2 + 8x + 15 = (x + 3)(x + 5) '--y---1 '--y---1 product factors 176 f Category II: Algebra and Functions Strategy Note Quadratics that occur often on the SAT are listed below. Memorize the different forms each quadratic can take. 1. (x + y)2 = (x + y)(x + y) = x 2 + 2xy + y2 f + 3)2 = x 2 + 6x + 9 1. (x 2. (x - y)2 = (x - y)(x - y) = x 2 - 2xy + y2 2. (x - 3)2 = x 2 - 6x + 9 3. (x + y)(x - y) = x 2 - y2 3. (x + 3)(x - 3) = x 2 - 9 SKILL SET Find the product or the square. 1. 3(x + 2) 2. y (y - 1) 3. (z + l)(z - 3) 5. (x - 1)2 6. (y + 2)2 7. 9. (p + q)(P - q) 10. (a + b)2 (a - 3)(a + 4. (b - 2)(b - 1) 8. (c - d)2 3) 11. (2k - 3)2 12. (2x + y)2 15. x 2 -x 16. m 2 + 2m + 1 19. x 2 + 6x + 9 20. a 2 Factor. 13. 2p + 4q 14. b 2 17. s2 - t 2 18. y2 - 2y + 3b + 1 MODEL QUESTIONS Model 1 If x 2 + y2 (A) -13 = 37 and xy = 24, what is the value of (x (B) -11 (C) 11 (D) 13 - y)2? (E) 61 Solution: Recognize that x 2 + y2 and xy can be found in (x - y)2. Rewrite. (x - y}2 = (x - y)(x - y) Multiply using the FOIL method. = x2 - Rearrange the terms to get x 2 + y2. = x 2 + y2 Sub-in the given values, and evaluate. = 37 - 2(24) = -11 Answer: B 2xy + y2 - 2xy - 8a + 16 I r If':·, Part 2: Equations = 14N3, x + Y = 21N, and N *- 0, what is x Model2 If x 2 - y2 (A) .Jv2 ~2 (B) (C) 3~2 - y in terms of N? (E) 14N 3 + 21N (D) 7N2 x 2 - y2 = 14N3 Solution: Factor the quadratic expression. Sub-in 21N for (x (x + y)(x - y) = 14N 3 21N (x - y) = 14N 3 + y). 3 2 14N (x-y)= - - =2N - 21N 3 Divide both sides by 21N. Answer: 177 B SAT-Type Problems 1. If x 2 + 81 (A) -81 = 6 x 27, then x could be (B) -9 (C) 0 (D) 3 (E) 14 2. If x = v'5 and y = 0, what is the value of (x + y) (x - y)? (A) -2 (D) (B) V35 V2 (C) 2 (E) 35 3. (3 + ab)(7 - ab) = (A) 21 - a 2 b2 (C) 21 + 4ab + 4ab - a 2 b 2 (E) 21 - ab 4. (5x - 3y)2 + (5x + 3y)2 = ..l.lI· .. (B) 16 (C) 8 (C) 13 (D) 16 (E) 26 (B) 0.1 (C) 1 (D) 7 (E) 10 8. If x 2 + 7x + 8 = (x + 3)(x + 4) + p, thenp = (B) 4 (C) 2 (D) -2 (E)-4 9. If x 2 - 3x - 2 = 0, then what is the value of 2x 2 - 6x - 11? (B) 50x 2 + 18y2 (C) 50x 2 - 30xy + 18y2 (D) 50x 2 + 15xy + 18y2 (E) 50x 2 + 30xy + 18y2 (A) 36 (B) 7 7. If 4x+3y 2 2 -- 10, w hat at iIS t h e 16x - 9y value of 4x - 3y? (A) 8 (A) 100x2 5. If x + y = 12 and x - y x2 _ y2 = (A) 3 (A) 0.01 (B) 21 (D) 21 x 2 + 5x + 6 ( ) x+2 rounded to the nearest whole number is 6. If x = 10.00001, then (A) -9 (B) -7 (C) 0 (D) 7 (E) 9 10. (2x + 3y)2 - (2x - 3y)2 = 1 then = -, 3 (A) 12x (D) (D) 4 12xY (B) 12y (C) 24x (E) 24xy (E) 2 ..... L.-------------_J Rational Expressions are handled the same way that fractions are handled in arithmetic. . Note, however, that just as fractions are meaningless when the denominator equals zero, the rational expression is meaningless when the denominator equals zero. We can never divide by zero. .1 is meaningless when a = a 7 mix - 2) 0. is meaningless when m when x = 2. SKIl-L SET Simplify. a + b 1. a-b a-b 4. ~+~ n m (x + y)2 . 7. z3 Z x+y b b+a 2. a a+b 5. 4x + 3x 5 7 8. 3p2 -'- 6p 3 ----;:'2' 2r 3 3. m r-m 6. c3 d 2 . c2 d5 9. a-b 2 r r - m (a - b)2 6 Solve for x. 1 2 10. 1+-=3 x 11. 1 x+2 1 -- 1 2 12. -+-=1 x x 3 Strategy Note Remember that the answer choices in the SAT may not be written in the form in which you have done your calculations. For example, your answer may be m + x , while the answer choice may be x m x + 1. = 0, or SAT-Type Problems 1. 4a-~ 3 2 -.! (A) 2a 3 (C) 2a - ~ 3 (B) 2a - 1 1 (E) 8a - .! ·33 (D) 2a - x3 . x4 . x5 6 = x n , then n = x (A) 2 (B) 6 (C) 10 (D) 54 2. If (E) 66 3. If ~ = 1, then:L + 5 = y 5 x (A) (B)~ 1 6 (C) 26 (D) 26 ~ 5 (E) 10 5 (~y 4. If a=/;O, then (: (A) --.L (B) 16 5 If x • a3 = - b 8 = ~1_ b - x (B) 1 (C) and a . b (A) bx (D) 1 Y 4 =/; ~ (D) ~ 16 (E) s. 4 1 0 then - 3 = 'a (C) ~ x b (E)--.L bx 6. If g and m are positive integers, then which of the following must be equal to .fL..? m + g (C) g + m m+m m+g (A)L+ 5 m +5 (B) g (D) g - m (E)L gm 2 m2 7. If x + 2x + 3x + 4x = 9, then x = x·x 9 1.)10 (B) 1 (E) 10 (D) 5 8. If...!!....- = ~, then which of the 25 n following could equal 50? (A) n 2 (D) (B) 50n 25 2 n2 - (C) 2n - 25 (E) 3n - 25 2 9. If -2 +2+ - +2 2 + - + 2 = 0, then x x x x (A) -2 (B) -1 (D) 0 (E) 1 (C) -.l 2 10. I f _8_ = 8 ,then what is the a+l 2a-2 . value of a? .) 3 (C) 1 (B) 2 (E) (D) 0 -.l 3 2 - = --3 11. I f - , then what is the y+2 y-3 value ofy? (A) -3 (B) -2 (D) 2 (E) 3 12. If a 2 = l, then c2 = C (A) l a (C) 0 = 13. If m 2 9 = Sr and r = lOt, then what (A)~m (B) (D)~m (E)~m !:-m 5 (C)~m 10 14. If rand s are positive integers and 1- + s = 1, then what is the value of s r (A) x = a (D) x> 1 9 2 b a then which of the following state ments must be true? is t in terms of m? 25 . 1 1 17. If 0 < a < 1 < b and x = - - -, b (B) x> 0 (E) 0 (C) x = 1 <x <2 18. If 1 + x = 1, then which of the g following is an expression for x in terms of g? in terms of r? (A)_I_ (B) 1 - r (A) r - 1 r (C) 1 - r 1+r r (D)_r_ (E)_r_ 1+r r - 1 r m i *" 0, then what is the value of y? (c)2 3m 3 (D) m 2 y , then what is 6 the ratio of x toy? (A) 6 to 5 (D) (E)g - 1 (A) -2 and -6 (B) -3 and -4 (C) 2 and 6 (D) 3 and 4 (E) 1 and 12 1 1 1 20. Solve - + - = p2 18 2p (E) 3m 2 3 6 (C) g - 1 g m 2 16. If ~x = (B)I-g 19. Solve 1- + ~2 = ~ 4 m -rn rri (A)_1_ (D) - g - g-1 h 15. If m+m+m - y = 1, were m m g -:-1 5 to 7 to 7 (E) 7 to 5 (B) 6 (C) 7 to 6 (A) -3 and -6 (B) -3 and 6 (C) -2 and 9 (D) 3 and -5 (E) 3 and 6 g -------------------------A radical equation is an equation with at least one radical expression containing a variable under the radical symbol. To solve a radical equation, use the following power I'ule: If x = y and n is a positive integer, then x n = y", Also recall that (~r = x. SAT-Type Problems All ofthe following problems are designed as Student-Produced Response Questions. 1. If vx=3 = 3, then what is the value of x? 4. If v5x - 1 + 2 = 10, then what is the value of x? 2. If v3x - 8 = 4, then what is the value of x? 5. If v6b + 4 = 20, then what is the value of x? 3. If 3v2x + 1 = 15, then what is the value of x? 6. Ifv3x + 3 = 3vx-1, then what is the value of x? 7. If Y20x = 2Y4x + 5, then what is the value of x? 9. If 2Y6X = V4X2, then what is the value of x? 8. If 5Y5x - 1 = 7V2x + 5, then what is the value of x? 10. If Y3x + 1 = x - 3, then what is the value of x? ~ ------------------ -----J An inequality states that one quantity is less than (or greater than) another. -2 < 3 x+2>x+l T T is less than is greater than SKILL SET Match the expression in column I with the phrase in column II. Column II Column I 1. A. k is less than O. O<k<1 B. k is greater than 2. k:> - I ' -1 but less than or equal to O. c. k is not equal to O. 3. k<O 4. -1 < k < D. k is greater than 0 but less than 1. 0 E. k is greater than 5. k=l=O or equal to -l. Solve the inequality. 6. 3x - 8 < 1 7. - 5x + 1 > - 9 8. 1 < 2a + 3 < 7 --------------------------------SAT-Type Problems 1. If 10 - x> 7, then x Can be any of these numbers except . (A) -5 (D) 0 (B) -3 (C) -2 (E) 3 2. If .!Q. < x, then which of the following x values could be x? (A) -10 (B) -5 (C) 1 (D) 2 (E) 5 3. If 0 < x < 1., which of the following 2 statements must be true? (A) 2x = 1 (D) x < x2 (B) x> x 2 (E) 2x > 1 x2 2 (C)x = - 4. If -1 < x < 0, then which of the following statements must be true? (A) 2x (D) x = -1 < x2 x2 2 (B) x> x 2 > (E) 2x (C) x = 1 (B) 12 < rt < 26 < rt < 15 (D) 35 < rt < 165 (C) 35 < rt < 55 (E) 55 < rt < 105 6. If a > b, c < b, and d > a, then which of the following is the correct relationship? (E) c < b<a <d <a < c<d <a < d < b (B) c (D) b < b< d <a <c <a <d (A) x < 1- (D) x < -1- (E) x > 1 8. If K > 1- (C) x > -! 3 3 3 3 = - ~, then which of the following inequalities is correct? K < K3 < K2 (D) K3 < K2 < K (B) < m2 < m3 (C) m 2 < m 3 < m . 2 (E) m 3 < m < m (A) m =0 (C) x < -II 2 11. If ~ > x, then which of the following 6 values could be x? (A) 6 (B) 3 (D) -3 (E) Cannot be determined (C) 0 12. If a and b are integers, and a < b < 0, which ofthe following must be true? I. aXb>O II. -b>-a 7. If 1 - 3x < 0, then which of the following contains all the values for x? (B) x (B) x 2 (A) 7 (C) b (A) x> 0 (D) x > 11- (E) x < 5. If 7 < r < 11 and 5 < t < 15, then (A) c 10. If3 - x < 3x + 3, which of the following must be true? III. 0 < l a < 1 II only (C) I and III only (D) II and III only (E) I, II, and III (A) I only (B) I and 17. If x > 1, then which of the following decreases as x increases? .L3. Ifx > y, and xy < 0, which of the following inequalities must be true? I. x> 0 I. II. y > 0 II. III. -1 III. ~< 0 x+1 y (A) I only (B) II only (C) III only (D) I and III only (E) I, II, and III (A) I only (B) II only III only (D) I and II only (E) I and III only (C) 14. If 1 :5 x :5 3 and 3 :5 Y :5 5, the 18. What are all the values of x for which (x - 3)(x + 5) < O? least possible average of Ix and Iy is -_. (A) (B)~ --.£ (C) 15 15 (E) (D) .! 3 > - 5 (B) x > 5 (C) x < 3 (D) -3 < x < 5 (E) -5 < x < 3 (A) x 1. 3 ~ 3 19. What are all the values of x for which (x + 6)(x + 3) < O? 15. If 1 :5 X :5 3 and 3 :5 Y :55, the greatest possible average of I and 1.. is x y (A) --.£ 15 (B) 1 x2 3x 2 - x ~ 15 (C) 1. 3 (D).! 3 (E) ~ 3 16. If a and b are integers and a + b > a - b, which of the following must be true? (A) a < 0 (B) b < 0 (D) b > 0 (E) b > a (C) a = b < x < 3 (B) -6 < x < -3 x < 3 (D) x < -3 (A) -6 (C) (E)x <-6 20. If x 2 - 3x + 4 > x 2 + 3x + 4, then which of the following best describes x? < 0 (B) x = 0 (D) x < -3 (E) x > 3 (A) x (C) x = 1
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