Select the approximate values of x that are solutions to f(x) = 0, where f(x) = -2x^2 + 4x + 3. A. {-0.67, 1.33} B. {-2, 4} C. {-2.00, -1.50} D. {-0.58, 2.58}

Question

Having trouble with this question. Please show me how to work it out. I have 4 more like this.

Answer 1

D. 

 

A = -2

B = 4

C = 3

 

x = (-B ± √(B² - 4AC))/(2A)

x = (-4 ± √(4² - 4(-2)(3))/(2(-2))

x = (-2 ± √(10))/-2

x = (approx.) 2.58, -.581