m(15+6)+m(6)=42

Solution for m(15+6)+m(6)=42 equation:

m(15+6)+m(6)=42

We simplify the equation to the form, which is simple to understand 
m(15+6)+m(6)=42

Simplifying terms in parentheses
m*(+21)+m*(6)=42

Reorder the terms in parentheses
+(+21m)+m*(6)=42

Remove unnecessary parentheses
+21m+m+*(+6+)=+42

Reorder the terms in parentheses
+21m+(+6m)=42

Remove unnecessary parentheses
+21m+6m=+42

We move all terms containing m to the left and all other terms to the right. 
+21m+6m=+42

We simplify left and right side of the equation. 
+27m=+42

We divide both sides of the equation by 27 to get m. 
m=1.55555555556