SOLUTION: Find the x-intercepts of the parabola with vertex (-7,45) and y-intercept (0,-200). write yiour anwser in this form : (x,y), (x2,y2). If necessary round to nearest hundredth

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: Find the x-intercepts of the parabola with vertex (-7,45) and y-intercept (0,-200). write yiour anwser in this form : (x,y), (x2,y2). If necessary round to nearest hundredth      Log On


   

Question 337643: Find the x-intercepts of the parabola with vertex (-7,45) and y-intercept (0,-200).
write yiour anwser in this form : (x,y), (x2,y2).
If necessary round to nearest hundredth
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Use the vertex form,
y=a%28x-h%29%5E2%2Bk
y=a%28x%2B7%29%5E2%2B45
Use the y-intercept to solve for a.
-200=a%280%2B7%29%5E2%2B45
49a%2B45=-200
49a=-245
a=-5
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y=-5%28x%2B7%29%5E2%2B45=0
5%28x%2B7%29%5E2=45
%28x%2B7%29%5E2=9
x%2B7=0+%2B-+3
x=-7+%2B-+3
highlight%28x=-10%29 and highlight%28x=-4%29
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