Question

If -2x²+5-8 is multiplied by 4x-9, what is the coefficient of x in the resulting polynomial?

A) -77
B) -45
C) -32
D) -13

Answer 1

-77 assuming you meant to write -2x^2+5x-8 instead of -2x^2+5-8

Explanation:

You could multiply it out and see...

(-2x^2+5x-8)(4x-9)

(-2x^2)(4x-9)+(5x)(4x-9)+(-8)(4x-9)

-8x^3+18x^2+20x^2-45x-32x+72

-8x^3+38x^2-77x+72

Coefficient of x^3 is -8

Coefficient of x^2 is 38

Coefficient of x is -77

Constant term is 72