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Question 74598:  anybody good at parabolas?
 
on my "Y" axis from 1 through 5 the top of the parbola (known as V(-3,4)) is at 4 where it begins its downward peak.
 
on the "X" axis the right leg comes through -1 curves through the "Y" axis of 4 and the left leg goes back down through -5 on the "x" axis.
 
Question:  Determine the standard equation of the parabola.
 
I know you people are whizzes and I would really be impressed. I have missed every question concering parabolas.
 
Thank you 
 Answer by stanbon(75887)      (Show Source): 
You can  put this solution on YOUR website! on my "Y" axis from 1 through 5 the top of the parbola (known as V(-3,4)) is at 4 where it begins its downward peak.
 
on the "X" axis the right leg comes through -1 curves through the "Y" axis of 4 and the left leg goes back down through -5 on the "x" axis.
 
Question:  Determine the standard equation of the parabola.
 
---------------------------- 
The V point is the vertex. 
The vertex form of this parabola that opens downward is (x-h)^2 = 4p(y-k) 
where (h,k) is the vertex. 
So, (x+3)^2=4p(y-4) 
When x=-5, y=0 so substitute and solve for "p". 
(-5+3)^2 = 4p(0-4) 
4=4p(-4) 
p=-1/4 
EQUATION: 
on my "Y" axis from 1 through 5 the top of the parbola (known as V(-3,4)) is at 4 where it begins its downward peak.
 
on the "X" axis the right leg comes through -1 curves through the "Y" axis of 4 and the left leg goes back down through -5 on the "x" axis.
 
Question:  Determine the standard equation of the parabola.
 
(x+3)^2=4(-1/4)(y-4) 
(x+3)^2 = -y+4 
y=-(x+3)^2+4 
In standard form: 
y=-x^2-6x-5 
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Cheers, 
Stan H. 
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