# Math

posted by
**Hannah** on
.

Find the critical values of P(x)

p(x)= (28+x)(8-x/4)

the answer was p=244-7x+8x-x^2/4

p=-x^2/4 + x + 244

p'= -x/2 +1 = 0

X=2

My question is, I do not understand how they got -7x + 8x at the beginning. I know (28)(8)=244 but I do not get the rest.