n+3n=-5(n+3)+6(1+n)

Solution for n+3n=-5(n+3)+6(1+n) equation:

n+3n=-5(n+3)+6(1+n)

We simplify the equation to the form, which is simple to understand 
n+3n=-5(n+3)+6(1+n)

Reorder the terms in parentheses
n+3n=+(-5n-15)+6*(1+n)

Remove unnecessary parentheses
+n+3n=-5n-15+6+*(+1+n+)

Reorder the terms in parentheses
n+3n=-5n-15+(+6+6n)

Remove unnecessary parentheses
+n+3n=-5n-15+6+6n

We move all terms containing n to the left and all other terms to the right. 
+1n+3n+5n-6n=-15+6

We simplify left and right side of the equation. 
+3n=-9

We divide both sides of the equation by 3 to get n. 
n=-3