Question 668793
y = 25-x^2


y = -x^2 + 25


y = -1*x^2 + 25


y = -1*(x-0)^2 + 25


The equatin is now in the form y = a(x-h)^2 + k


This is known as vertex form, where (h,k) is the vertex


We can see that h = 0 and k = 25


So the vertex is (0, 25)


Here's the graph (using a graphing calculator)


{{{ drawing(500, 500, -10, 10, -5, 30,
 graph( 500, 500, -10, 10, -5, 30,0,25-x^2	)

)}}}