Question 293618
Standard "vertex form" is
y= a(x-h)^2+k
where (h,k) is the vertex
.
-x^2+10x+5
First group the x terms:
-(x^2-10x)+5
Complete square:
-(x^2-10x+__)+5
-(x^2-10x+25)+5+25
-(x-5)^2+30
So, the vertex is at:
(5,30)