Select the approximate values of x that are solutions to f(x) = 0, where f(x) = -7x2 + 4x + 3.

Question

{–2.33, 1.33} {-7, 4} {–0.57, –0.43} {–0.43, 1.00}

Answer 1

f(x) = - 7X² +4X +3 

 

f(x) = 0

 

-7X²  + 4X  + 3 = 0

 

 -7 X² + 7X - 3X + 3 = 0

 

 - 7X ( X - 1 ) - 3 ( X - 1 ) =0

 

   Answer D is correct.

 

  ( X - 1 ) ( -7X - 3 ) =0

 

   X - 1 = 0   X =1

 

  -7X - 3 = 0

 

  - 7X = 3 

 

    X = - 3/ 7