Which equation describes the parabola, given it has vertex (−2, 0) and passes through (0, 8)?
A y = 2(x + 2)²
B y = (x + 2)²
C y = 2(x − 2)²
D y = −(x + 2)²
Explanation
Vertex form y = a(x − h)² + k with (h, k) = (−2, 0): y = a(x + 2)². Pass (0, 8): 8 = a(2)² = 4a → a = 2. y = 2(x + 2)².