SOLUTION: Find a formula for the quadratic function whose graph has y-intercept at y=13 and zeros at x=3 and x=5.

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Question 1124677: Find a formula for the quadratic function whose graph has y-intercept at y=13 and zeros at x=3 and x=5.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
(x-3)(x-5) are factors
The axis of symmetry is at x=4.
See if a numeric factor k is needed
k(x^2-8x+15)=0
f(x)=a(x-3)(x-5)
we know when x=0, f(x)=13
13=a(-3)(-5)=15a
therefore, a=(13/15)
(13/15)(x^2+8x+15)=0 ANSWER
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