Question 972721
-x^2 +8x-15
the maximum occurs at an x-value of -(b/2a), where b=8, and a=-1   -(8/-2)=+4
f(4)=-16+32-15=1

-x^2+2x-15
a=-1 b=2   -(b/2a)= -(2/-2) = 1
f(1)=-1+2-15=-14  

Function 1 has the higher maximum

{{{graph (300,300,-10,10,-20,10,-x^2+8x-15,-x^2+2x-15)}}}