Question 391331: given that the vertex of parabola is 2,-9 and that the same parabola has an x- intercept at 5, find the value of "a" Answer by ewatrrr(24785) (Show Source):
Hi,
Using the vertex form of a parabola, where(h,k) is the vertex
vertex of parabola is Pt(2,-9)
y = a(x-2)^2 - 9 |Using x-intercept Pt(5,0) to solve for a
0 = a*3^2 - 9
9 = 9a
a = 1
Graphing y = (x-2)^2 - 9
