Jon P. answered • 02/08/15

Tutor

5.0
(171)
Knowledgeable Math, Science, SAT, ACT tutor - Harvard honors grad

The equation for a parabola is y = k(x-a)

^{2}+ b, where (a, b) is the vertex.Since the vertex is at (2,0), this means that the equation is y = k (x - 2)

^{2}+ 0 = k (x - 2)^{2}Since it goes through (1,3), plug x=1 and y=3 into that equation to find k:

y = k (x - 2)

^{2}3 = k (1 - 2)

^{2}3 = k (-1)

^{2}3 = k

So the equation is y = 3(x - 2)

^{2}