SOLUTION: How to write quadratic function if vertex is (-3,-3) and y intercept is (0,6)

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Question 1146276: How to write quadratic function if vertex is (-3,-3) and y intercept is (0,6)
Found 3 solutions by ankor@dixie-net.com, josgarithmetic, MathTherapy:
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
How to write quadratic function if vertex is (-3,-3) and y intercept is (0,6)
:
Using this form, ax^2 + bx + c = y
x=-3, c=6, y=-3, Assume a=1
9(1) - 3b + 6 = -3
find b
-3b + 15 = -3
=3b = -3 -15
-3b = -18
b = -18/-3
b = 6
The equation: y = x^2 + 6x + 6
Graphically
+graph%28+300%2C+200%2C+-6%2C+5%2C+-5%2C+7%2C+x%5E2%2B6x%2B6%29+

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
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quadratic function if vertex is (-3,-3) and y intercept is (0,6)
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y=a%28x-%28-3%29%29%5E2-3
y=a%28x%2B3%29%5E2-3
y%2B3=a%28x%2B3%29%5E2
a=%28y%2B3%29%2F%28x%2B3%29%5E2
substitute given point:
a=%286%2B3%29%2F%280%2B3%29%5E2
a=9%2F9
a=1
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highlight%28y=%28x%2B3%29%5E2-3%29-------------you could multiply and simplify if you want to.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

How to write quadratic function if vertex is (-3,-3) and y intercept is (0,6)
Equation of a parabola in vertex-form : matrix%281%2C3%2C+y%2C+%22=%22%2C+a%28x+-+h%29%5E2+%2B+k%29, with:
(h, k) being the coordinates of the vertex of the parabola
(x, y) being a point on the parabola
"a" being the width and location of the parabola
matrix%281%2C3%2C+6%2C+%22=%22%2C+a%280+-+-+3%29%5E2+-+3%29 ------ Substituting (- 3, - 3) for (h, k) and (0, 6) for (x, y) in order to determine the value of "a."
6 = 9a - 3
6 + 3 = 9a
9 = 9a
matrix%281%2C5%2C+9%2F9%2C+%22or%22%2C+1%2C+%22=%22%2C+a%29
Equation of parabola in vertex-form: highlight_green%28matrix%281%2C3%2C+y%2C+%22=%22%2C+%28x+%2B+3%29%5E2+-+3%29%29