Answer:
therefore y= - (x-2)^2 + 5
Explanation:
u do this by using this format here ..,
y=a(x-h)^2+k
sub in the vertex points as h=2 and k = 5 , since the 2 is positive its sign will be -2 in the brackets because when solving for x-2=0 it is x=2
y=a(x-2)^2+5
then with your (0,1) points plug that in as y and x
1=a(0-2)^2+5
1=a(-2)^2+5
1=4a+5
1-5=4a
-4=4a
a=-1
therefore y= - (x-2)^2 + 5