# 12n=9(n+10) - Algebra - Solve Equation

by Lilly
(Brooklyn, NY)

Solve Equation for n.

12n = 9(n + 10)

Begin by expanding the expression on the right hand side of the equation using the distributive law.

This will “remove the parentheses”.

### Comments for 12n=9(n+10) - Algebra - Solve Equation

 Dec 18, 2011 Solve Equation - 3 steps by: Staff Question: by Lilly (Brooklyn, NY) 12n=9(n+10) Answer: 12n = 9(n + 10) Begin by expanding the expression on the right hand side of the equation using the distributive law. This will “remove the parentheses”. 12n = (9*n) + (9*10) 12n = 9n + 90 Subtract 9n from each side of the equation. This will “remove the variable n from the right side of the equation”. 12n - 9n = 9n + 90 - 9n 3n = 9n + 90 - 9n 3n = 9n - 9n + 90 3n = 0 + 90 3n = 90 Divide each side of the equation by 3. This will “remove the 3 from the left side of the equation”. 3n/3 = 90/3 n*(3/3) = 90/3 n*(1) = 90/3 n = 90/3 n = 30 the FINAL ANSWER is: n = 30 Check the answer by substituting 30 for n in the original equation: 12n = 9(n + 10) 12*30 = 9(30 + 10) 360 = 9(30 + 10) 360 = 360, OK → n = 30 is a VALID solution Thanks for writing. Staff www.solving-math-problems.com