Question 1190598
The equation in vertex form is

y=a(x-h)^2+k

 Vertex :(2,0); point (1,4)

y= a(x-2)^2+0

plug values of the point  +0
4 = a(1-2)^2+0

4= a(1)
a=4

y = 4(x-2)^2

 *[illustration vertex_form.png].