SOLUTION: Find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20). Write your answer in this form: (x1,y1),(x2,y2).

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20). Write your answer in this form: (x1,y1),(x2,y2).      Log On


   

Question 936967: Find the x-intercepts of the parabola with vertex (-3,16) and y-intercept (0,-20).
Write your answer in this form: (x1,y1),(x2,y2).
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
y=a%28x-%28-3%29%29%5E2%2B16
y=a%28x%2B3%29%5E2%2B16
When x=0,
y=a%280%2B3%29%5E2%2B16=-20
9a%2B16=-20
9a=-36
a=-4
So then,
y=-4%28x%2B3%29%5E2%2B16
0=-4%28x%2B3%29%5E2%2B16
4%28x%2B3%29%5E2=16
%28x%2B3%29%5E2=4
x%2B3=+0+%2B-+2
x=-3+%2B-+2
x=-1 and x=-5
Now use the x values to generate y values in y=-4%28x%2B3%29%5E2%2B16 and your answer is complete.