select the approximate values of x

Question

select the approximate values of x that are the solutions to f(x)=0, where f(x)= -6x^2+2x+6

 

A) {-0.85, 1.18}

 

B) {-6, 2}

 

C) {-0.33, -1.00}

 

D) {-1.00, 0.33}

Answer 1

By the quadratic formula we have

x=[-2±√(4-4×(-6)×6)]/-12 = [-2±√(148)]/-12=[-2±12.16552506]/-12

x = -.85 and 1.18