The graph of quadratic function f has zeros of -8 and 4 and a maximum at (-2,18). What is the value of a in the functions equation
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Hello,
Answer D
-8 and 4 are zeros ==> y=k*(x+8)(x-4)=kx²+4kx-32k
(-2,18) is a point of the curve:
18=k*(-2)²-8k-32k
-36k=18
k= - 1/2