Question 703935: Find the equation of the parabola with vertex (-2,0) and y intercept 4.
Can you please help me? Thanks so much in advance
Found 2 solutions by josmiceli, Edwin McCravy: Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! First write down the general form
of a parabola, which is:

When in this form, the x-coordinate of the vertex
is at 
You are given that the vertex is at ( -2,0 ), so I can say



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So far, I have:

The y-intercept occurs where , so


You are given that the y-intercept is , so

----------------
So far, I have:

Now I go back to the vertex at ( -2,0 )





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Now I have all I need to write the equation

answer
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check:
Does it go through ( 0,4) ? ( the y-intercept )



OK
Here's the plot:

Answer by Edwin McCravy(20054) (Show Source):
You can put this solution on YOUR website! Find the equation of the parabola with vertex (-2,0) and y intercept 4
y = a(x-h)² + k
Substitute (h,k) = (-2,0) and (x,y) = (0,4)
4 = a(0-(-2))² + 0
4 = a(2)²
4 = 4a
1 = a
Substitute for just a, h and k, not x or y
y = a(x-h)² + k
y = 1(x-(-2))² + 0
y = (x+2)²
Or you can multiply that out
y = x²+4x+4
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