SOLUTION: a quadratic function has the following characteristics x=1 is the equation for the axis of symmetry x=-1 is an x-intercept y=-4 is the minimum value Determine the y-interce

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Question 734571: a quadratic function has the following characteristics
x=1 is the equation for the axis of symmetry
x=-1 is an x-intercept
y=-4 is the minimum value
Determine the y-intercept of the parabola
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
The axis of symmetry and the minimum value give you the vertex, (1, -4) = (h, k). You can begin developing an equation as y=a%28x-1%29%5E2-4.

Could you try to use the given x intercept to solve for and find the value for "a"? You would then have the equation for this parabola. Let x=0 and find y.

How does this work: x intercept is at -1.
0=a%28-1-1%29%5E2-4
0=a%2A%28-2%29%5E2-4
0=4a-4
-4a=-4
a=1.

Parabola is highlight%28y=1%2A%28x-1%29%5E2-4%29. y intercept would be at x=0.
y=%280-1%29%5E2-4
y=1-4
highlight%28y=-3%29.