7(b-3)+3(b+12)=9(b+2)

Solution for 7(b-3)+3(b+12)=9(b+2) equation:

7(b-3)+3(b+12)=9(b+2)

We simplify the equation to the form, which is simple to understand 
7(b-3)+3(b+12)=9(b+2)

Reorder the terms in parentheses
+(+7b-21)+3*(b+12)=9*(b+2)

Remove unnecessary parentheses
+7b-21+3+*(+b+12+)=+9+*(+b+2+)

Reorder the terms in parentheses
+7b-21+(+3b+36)=9*(b+2)

Remove unnecessary parentheses
+7b-21+3b+36=+9+*(+b+2+)

Reorder the terms in parentheses
+7b-21+3b+36=+(+9b+18)

Remove unnecessary parentheses
+7b-21+3b+36=+9b+18

We move all terms containing b to the left and all other terms to the right. 
+7b+3b-9b=+18+21-36

We simplify left and right side of the equation. 
+1b=+3

We divide both sides of the equation by 1 to get b. 
b=3