SOLUTION: find the x-intercepts of the parabola with vertex (6,27) and y intercept (0,-81) round to the nearest hundreth

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Question 750088: find the x-intercepts of the parabola with vertex (6,27) and y intercept (0,-81) round to the nearest hundreth
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
Doing on paper is easier. Try this approach.

Using standard form, y=a%28x-h%29%5E2%2Bk, your vertex gives you:
y=a%28x-6%29%5E2%2B27

The y intercept given allows you this relation:
-81=a%280-6%29%5E2%2B27
-81-27=36a
36a=-108
a=-3

What is the equation for the described parabola?
highlight%28y=-3%2A%28x-6%29%5E2%2B27%29
All you do next is just solve this for x using uncomplicated algebra steps with letting y=0.
Solve for x in -3%2A%28x-6%29%5E2%2B27=0.