Question

The vertex of a quadratic function is (6, 2), and the y-intercept of the function is (0, −70). The equation of the function in vertex form, f(x)=a(x−h)2+k, is shown.

−70=a(0−6)2+2

What is the value of a?

−6
−2
2
6

Answer 1

(0−6)^2 = 36, so −70 = 36a + 2 → 36a = −72 → a = −72/36 = −2.

Answer: −2