Algebra 2B Concepts question

Question

Given f(x) = x2 – 4x – 2 and g(x) = 2x2 + 4x + 9, find (f – g)(x).

 

A.)-3x^2-8x-11

 

B.)-3x-11

 

C.)-x-11

 

D.)-x^2-8x-11

 

 

Answer 1

Given f(x) = x² – 4x – 2 and g(x) = 2x² + 4x + 9, find (f – g)(x).

 

      (f-g)(x) = f(x) - g(x)

 

      = (x² – 4x – 2) - (2x² + 4x + 9)

 

      = x² - 4x - 2 - 2x² - 4x - 9

 

Gather and add like terms:

 

      =  x² - 2x² - 4x - 4x - 2 - 9

 

      = -x² - 8x - 11