Упростите выражение (m+m+m)*(n+n+n)

Question

Упростите выражение (m+m+m)*(n+n+n)

Answer 1

1) m+m+m=3m
2) n+n+n=3n
(m+m+m)*(n+n+n)=3m*3n=9mn

Answer 2

3m×3n= 9 mn ....................