SOLUTION: Find a possible formula for the quadratic function whose graph has x intercepts 4 and 8 and y intercept 30 y=?

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Question 940463: Find a possible formula for the quadratic function whose graph has x intercepts 4 and 8 and y intercept 30
y=?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Using the x-intercepts, it would look like,
y=a%28x-4%29%28x-8%29
So when x=0, using the y-intercept,
30=a%28-4%29%28-8%29
a=30%2F32
a=15%2F16
So then,
y=%2815%2F16%29%28x-4%29%28x-8%29
y=%2815%2F16%29%28x%5E2-12x%2B32%29