Posted by Jennifer on .
I have a parabola that I have to write as an equation I found the vertex as (3,2) and the following points (4,1)(2,1),(5,2),(1,2).
I can't seem to come up with the correct equation. I'm using the formula y=a(hk)^2+k but I'm not doing something right. Can anyone help me?

Algebra 
Jai,
the formula is wrong. it should be
y = a(xh)^2 + k
where (h,k) is the center
then to solve for a, you choose one of the points to substitute for the value of x and y. for instance you choose (4,1):
y = a(xh)^2 + k
1 = a(4+3)^2  2
then solve for a.
if you want to make sure that you got the correct points on the parabola, if they are substituted in the equation, they should give the same value of a.
hope this helps~ :)