SOLUTION: Find the x-intercepts of the parabola with vertex (4,-1) and y-intercept (0,15).

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Question 936451: Find the x-intercepts of the parabola with vertex (4,-1) and y-intercept (0,15).
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
y=a%28x-4%29%5E2-1
So when x=0,
15=a%280-4%29%5E2-1
15=a%2816%29-1
16a=16
a=1
So,
y=%28x-4%29%5E2-1
%28x-4%29%5E2=1
x-4=0+%2B-+1
x=4+%2B-+1
x=3 and x=5