Question

Find the product: (r+2)(r-5)(r-2)(r+5) Please show all steps. 15 points.

Answer 1

Hello from MrBillDoesMath!

Answer:

r^4- 29r^2 + 100

Discussion:

Rearrange the terms in the product as follows:

(r+2)(r-2) *  (r-5)(r+5)  =

(r^2 - 4) * (r^2-25) =

f^4 - (25+4)r^2 + 4*25 =

r^4- 29r^2 + 100

Thank you,

MrB

Answer 2

by rearranging and foiling them

(r+2)(r-2)(r+5)(r-5)

${r }^{2} - 4$

${r}^{2} - 25$

now foil them

r^4-25r^2-4r^2+100

r^4-29r^2+100