SOLUTION: How do you graph x^2/81 + 4y/9 = 1

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Question 602928: How do you graph x^2/81 + 4y/9 = 1
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

How do you graph x^2/81 + 4y/9 = 1 

Solving for y = -(1/36)x^2 + 9/4



the vertex form of a parabola opening up or down:

 y=a%28x-h%29%5E2+%2Bk where(h,k) is the vertex.

y = -(1/36)x^2 + 9/4  

a<0, parabola opens downward

Vertex is Pt(0,9/4) 

when y = 0, (1/36)x^2 = 9/4  and x^2 = 81 or x = ± 9