Section 6.2 (pages 332–333)
1.D 3.B 5. 7. 9.prime
- 15.prime
27.prime 29. 31.
- 45.She did not factor
the polynomial completely. The factor can be factored
further into giving the final form as
Section 6.3 (pages 337–339)
1.A, D 3.B, C 5.The sum of two squares can be factored
if the binomial terms have a common factor greater than 1.
69.The product must equal
Multiply to verify this.
70.Start by factoring as a difference of squares.
71.
12 x+y 21 a-b 2 81. 1 p+ 721 p- 32
18 m- 9 n 218 m+ 9 n- 64 m^2 - 72 mn- 81 n 22
1 t- 3212 t+ 1214 t 2 - 2 t+ 12
13 a- 4 b 219 a^2 + 12 ab+ 16 b^2 + 52
15 p+ 2 q 2125 p^2 - 10 pq+ 4 q 2 + 5 p- 2 q 2
1 x^2 +xy+y^221 x^2 - xy+y^22
x 4 +x^2 y^2 +y 4 x^4 +x^2 y^2 +y^4.
1 x^2 - y^221 x^4 +x^2 y^2 +y^42 ; 1 x-y 21 x+y 21 x^4 +x^2 y^2 +y^42
1 x^2 +xy+y^221 x^2 - xy+y^22
1 x-y 21 x^2 +xy+y^221 x+y 21 x^2 - xy+y^22
15 y^2 +z 2125 y^4 - 5 y^2 z+z^221 x^3 - y^321 x^3 +y^32 ;
1 m^2 - 521 m^4 + 5 m^2 + 252 13 - 10 x^3219 + 30 x^3 + 100 x^62
1 y+z+ 421 y^2 + 2 yz+z^2 - 4 y- 4 z+ 162
312 n+ 3 p 214 n 2 - 6 np+ 9 p^22
17 p+ 5 q 2149 p^2 - 35 pq+ 25 q 22
14 g- 3 h 2116 g 2 + 12 gh+ 9 h 22
15 x- 62125 x^2 + 30 x+ 362 1 x- 2 y 21 x^2 + 2 xy+ 4 y^22
110 +y 21100 - 10 y+y^2212 x+ 1214 x^2 - 2 x+ 12
16 - t 2136 + 6 t+t 22 1 x+ 421 x^2 - 4 x+ 162
1 a-b+ 422 1 x- 321 x^2 + 3 x+ 92
1 x+y- 121 x-y+ 12 217 m+ 3 n 22 1 p+q+ 122
14 m- 1 +n 214 m- 1 - n 2 12 r- 3 +s 212 r- 3 - s 2
1 p^2 + 1621 p+ 421 p- 42 1 k- 322 12 z+w 22
1 y+z+ 921 y+z- 92 14 +x+ 3 y 214 - x- 3 y 2
213 a+ 7 b 213 a- 7 b 2 414 m^2 +y^2212 m+y 212 m-y 2
1 p+ 421 p- 42 15 x+ 2215 x- 22
y^3 + 27
14 x^2 + 3214 x^2 + 12 9 x^2 - 25 p^2 + 6 pq+ 9 q 2
1 p^2 - 821 p^2 - 22 12 x^2 + 321 x^2 - 62
1 p+q 221 p+ 3 q 2 1 z-x 221 z+ 2 x 2
13 m+ 3 p+ 521 m+p- 42 1 a+b 221 a- 3 b 21 a+ 2 b 2
16 p^3 - r 212 p^3 - 5 r 2 15 k+ 4212 k+ 12
212 x+ 52 , 212 x+ 521 x- 22.
14 x+ 102
13 y 1 y+ 421 y- 12 3 p 12 p- 122
2 xy^31 x- 12 y 22 6 a 1 a- 321 a+ 52
- 51 a+ 6213 a- 42 - 11 x 1 x- 621 x- 42
12 xz- 1213 xz+ 42 314 x+ 5212 x+ 12
14 k+ 3215 k+ 82 13 a- 2 b 215 a- 4 b 2 16 m- 522
- 16 m- 521 m+ 32 15 x- 6212 x+ 32
1 a+ 5 b 21 a- 7 b 2 1 a- 6 b 21 a- 3 b 2
1 y- 321 y+ 102 1 p+ 821 p+ 72
Section 6.4 (pages 342–343)
- 7.prime 9.
- 61.prime
Connections ( page 349) 1. 2. 3.
Section 6.5 (pages 350–354)
1.First rewrite the equation so that one side is 0. Factor the other side
and set each factor equal to 0. The solutions of these linear equations are
solutions of the quadratic equation. 3. 5.
- 47.By dividing each side by a variable expression, she “lost” the
solution 0. The solution set is 49.
- 47.By dividing each side by a variable expression, she “lost” the
- 55.width: 16 ft; length: 20 ft
57.base: 12 ft; height: 5 ft 59.50 ft by 100 ft 61. and or
5 and 6 63.length: 15 in.; width: 9 in. 65.5 sec 67.
- 55.width: 16 ft; length: 20 ft
73.Lappears on both sides of the equation. 75.
77.
78.
ƒ 1 x 2 =- 16 x^2 + 80 x+ 100
5 - 0.5, 4 6
y=
- x
w- 3 , or y=
x
r= 3 - w
- 2 k- 3 y
a- 1 , or r=
2 k+ 3 y
1 - a
6 14 sec
- 6 - 5
E- 32 , 154 F E- 23 , 21 F
E- 34 , 0, 34 F. E- 21 , 6F
E-^43 , 0, 34 F E- 25 , -1, 1F 5 - 3, 3, 6 6
E-^12 , 6F 5 1, 6 6 E- 21 , 0, 5F 5 - 1, 0, 3 6
5 - 2, 2 6 5 - 3, 3 6 536 E- 34 F 5 - 4, 2 6
5 - 3, 4 6 5 - 5, - 51 F 5 - 4, 0 6 5 0, 6 6
5 - 2, 5 6 5 - 6, - 36 E-^12 , 4F E- 31 , 54 F
5 - 10, 5 6 E- 38 , 25 F
5 - 1, 7 6 536 5 - 2, 2 6
1 m+n- 521 m-n+ 12 E- 32 F 506 5 - 106
12 r-t 21 r 2 - rt+ 19 t 22 1 x+ 321 x 2 + 121 x+ 121 x- 12
1 p+ 8 q- 522 17 m 2 + 1213 m^2 - 52
4 rx 13 m^2 +mn+ 10 n 22 17 a- 4 b 213 a+b 2
21 x+ 421 x- 52 8 mn 215 p+ 9215 p- 92
1 x- 2 m-n 21 x+ 2 m+n 2 6 p^313 p^2 - 4 + 2 p^32
1 m-n 21 m^2 +mn+n 2 +m+n 2
4 pq 12 p+q 213 p+ 5 q 2 314 k^2 + 9212 k+ 3212 k- 32
814 + 5 z 2116 - 20 z+ 25 z^2215 r-s 212 r+ 5 s 2
6 z 12 z^2 - z+ 32 1614 b+ 5 c 214 b- 5 c 2
1 p+ 121 p^2 - p+ 12 18 m+ 25218 m- 252
1 x+ 721 x- 52 125 +x^2215 - x 215 +x 2
13 m- 5 n 22 1 k- 921 q+r 2 16 z^2 x 1 zx- 22
9 m 1 m- 5 + 2 m^22213 m- 10219 m^2 + 30 m+ 1002
1 x- 1021 x^2 + 10 x+ 1002 1 p+ 2214 +m 2
3 pq 1 a+ 6 b 21 a- 5 b 2 16 b+ 121 b- 32
110 a+ 3 b 2110 a- 3 b 2 3 p^21 p- 621 p+ 52
A-14 Answers to Selected Exercises
–100
010
300
f(x) = –16x^2 + 80x + 100 79.200 ft; 2.5 sec 80.about 6 sec
81.in the approximate interval
82.
- 85.- 87.^3675
3
4 m^4 n^3
4 p
1 0.7, 4.3 2 ƒ 1 x 2 =- 16 x^2 + 100 x