we have that
f(x) = –4x²
+ 24x + 13
we know that
The vertex form for a parabola that opens up or down is:
f(x) = a(x - h)^2 + k
in the given equation,
a=-4, therefore we add zero to the original equation in the form of 4h²
−4h²
f(x) = –4x² + 24x + 4h²−4h² +13
Factor 4 out of the first 3 terms and group them
f(x) = –4*(x² -6x +h²) +4h² +13
We can find the value of h by setting the middle term equal to -2hx
−2hx=−6x
h=3 and 4h²
=36
f(x) = –4*(x² -6x +9) +36 +13
we know that the term (x² -6x +9) is equals to------> (x-3)²
so
f(x) = –4*(x-3)² +49
the answer isf(x) = –4*(x-3)² +49