Question

Hasil dari (2r-7s)-(8s-r)(r-2s)=

Answer 1

(2r-7s)-(8sr-16s2-r2+2sr)
(2r-7s)-(10sr-16s2-r2+2sr)
2r-7s-10sr+16s2-r2
-r2+16s2-10rs+2r-7s

Answer 2

(2r - 7s) - (8s - r) (r - 2s)
= 2r - 7s  - (8s × r) (8s × -2s) (-r × r) (-r × -2s)
= 2r - 7s - (8rs - 16s² - r² + 2rs)
= 2r - 7s - 8rs + 16s² + r² - 2rs
= r² + 16s² + 2r - 7s - 8rs - 2rs
= r² + 16s² + 2r - 7s - 10rs