Question

Ramiro drew the graph below.

On a coordinate plane, a parabola opens up and has a vertex at (4, 0). It goes through (2, 4) and (6, 4).

Which equation represents the data in the graph?
y = x squared minus 8 x + 16
y = 5.5 x squared minus 0.5 x + 4
y = x squared + 4 x + 4
y = 2.5 x squared minus 0.5 x + 4

Answer 1

Vertex form: y = a(x - 4)^2 because the vertex is (4,0). Use (2,4): 4 = a(2 - 4)^2 = 4a, so a = 1. Thus y = (x - 4)^2 = x^2 - 8x + 16.