Доказать тождество: 4m-(m-4)+(5-2m)=m+9

Question

Доказать тождество: 4m-(m-4)+(5-2m)=m+9

Answer 1

4m - ( m - 4 ) + ( 5 - 2m ) = m + 9
4m - m + 4 + 5 - 2m = m + 9
m + 9 = m + 9

Answer 2

4m-(m-4)+(5-2m)=m+9
4m-m+4+5-2m=m+9