SOLUTION: HELP! I have been working on this for a long time and keep getting wrong answers. I need to write an equation in vertex form when I know that I the vertex at (-2,4)and a poin

Algebra ->  Rational-functions -> SOLUTION: HELP! I have been working on this for a long time and keep getting wrong answers. I need to write an equation in vertex form when I know that I the vertex at (-2,4)and a poin      Log On


   



Question 610137: HELP! I have been working on this for a long time and keep getting wrong answers.
I need to write an equation in vertex form when I know that I the vertex at
(-2,4)and a point (3,-1). I have gotten an answer of: f(x)=1/5(x-2)^2 + 4 but this is wrong.
Thanks so much!

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 
Hi,
Yes, Using the Vertex Form for a Parabola Opening Up and Down: y = a(x-h)^2 + k Does not work
Using the vertex form of a parabola opening right and left, x=a%28y-k%29%5E2+%2Bh where(h,k) is the vertex
V(-2,4);P(3,-1)
x = a(y-4)^2 -2
3 = a(-5)^2 -2
5/25 = a
1/5 = a
+x+=+%281%2F5%29%28y-4%29%5E2+-2+,this is the Vertex form for parabola opening right and or left ( in this case highlight%281%2F5%29>0, opens right.