224 Answer Key
- False
- False
- False
- False
- False
- − a − b
= −1a − 1b
= −1(a + b)
= −(a + b) - −3x^2 + 6 x − 9
= −3 ⋅ x^2 − 3 ⋅ −2x − 3 ⋅ 3
= −3(x^2 − 2x + 3) - 3 − x
= −1x + 3
= −1 ⋅ x −1 ⋅ −3
= −1(x − 3)
= −(x − 3) - 24x^9 y^2 − 6x^6 y^7 z^4
= 6 x^6 y^2 ⋅ 4 x^3 − 6x^6 y^2 ⋅ y^5 z^4
= 6 x^6 y^2 (4x^3 − y^5 z^4 ) - −45x^2 + 5
= −5 ⋅ 9 x^2 − 5 ⋅ −1
= −5(9x^2 − 1)
= −5(3x + 1)(3x − 1) - a^3 b − ab + b
= b(a^3 − a + 1) - 14x + 7 y
= 7 ⋅ 2 x + 7 ⋅ y
= 7(2x + y)
13. x(2x − 1) + 3(2x − 1)
= (2x − 1)(x + 3)
14. y(a + b) + (a + b)
= (a + b)(y + 1)
15. x(x − 3) + 2(3 − x)
= x(x − 3) − 2(x − 3)
= (x − 3)(x − 2)
16. cx + cy + ax + ay
= c(x + y)+ a(x + y)
= (x + y)(c + a)
17. x^2 − 3x − 4 = (x − 4)(x + 1)
18. x^2 − 49 = (x + 7)(x − 7)
19. 6x^2 + x − 15 = (3x + 5)(2x − 3)
20. 16x^2 − 25y^2 = (4x + 5 y)(4x − 5y)
21. 27x^3 − 64 = (3x − 4)(9x^2 + 12 x + 16)
22. 8a^3 + 125 b^3 = (2a + 5 b)(4a^2 − 10ab +
25 b^2 )
23. 2x^4 y^2 z^3 − 32x^2 y^2 z^3
= 2 x^2 y^2 z^3 ⋅ x^2 − 2x^2 y^2 z^3 ⋅ 16
= 2 x^2 y^2 z^3 (x^2 − 16)
= 2 x^2 y^2 z^3 (x + 4)(x − 4)
24. a^2 (a + b) − 2ab(a + b) + b^2 (a + b)
= (a + b)(a^2 − 2ab + b^2 )
= (a + b)(a − b)^2
Chapter 12 Factoring Polynomials
Exercise 12