Question

Which functions have an axis of symmetry of x = -2? Check all that apply. A. f(x) = x^2 + 4x + 3 B. f(x) = x^2 - 4x - 5 C. f(x) = x^2 + 6x + 2 D. f(x) = -2x^2 - 8x + 1 E. f(x) = -2x^2 + 8x - 2

Answer 1

Hey there! The answer to this question is

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Answer 2

A. f(x) = x^2 + 4x + 3

D. f(x) = -2x^2 - 8x + 1

Explanation:

The axis of symmetry is found by h = -b/2a where ax^2 +bx +c

A. f(x) = x^2 + 4x + 3

h = -4/2*1 = -2 x=-2

B. f(x) = x^2 - 4x - 5

h = - -4/2*1 = 4/2 =2 x=2 not -2

C. f(x) = x^2 + 6x + 2

h = -6/2*1 = -3/2 = x=-3/2 not -2

D. f(x) = -2x^2 - 8x + 1

h = - -8/2*-2 = 8/-4 =-2 x=-2

E. f(x) = -2x^2 + 8x - 2

h = - 8/2*-2 = -8/-4 =2 x=2 not -2