Question

How do you factor the expression `20r^2 + 8rs + 25rs + 10s^2`?

Answer 1

(5r + 2s)(4r + 5s)

Explanation:

`f(r,s) = (20r^2 + 8rs) + (25rs + 10s^2) =`
= 4r(5r + 2s) + 5s(5r + 2s) = (5r + 2s)(4r + 5s)