SOLUTION: If (-3,4) is the vertex of the curve of the the function f , -5 is one of the roots of the equation of (x)=0 , then the other root is??

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Question 907888: If (-3,4) is the vertex of the curve of the the function f , -5 is one of the roots of the equation of (x)=0 , then the other root is??
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Using the generic vertex form,
f%28x%29=a%28x-h%29%5E2%2Bk
f%28x%29=a%28x-%28-3%29%29%5E2%2B4
f%28x%29=a%28x%2B3%29%5E2%2B4
When x=5, f%28x%29=0
%285%2B3%29%5E2=%28x%2B3%29%5E2
Take the square root of both sides, use the negative square root.
-8=x%2B3
x=-11