# Question #31888

Dec 14, 2017

n = -6 or -3

#### Explanation:

Start by adding 18 + 9n to both sides. This gives you the classic quadratic equation that you can go to work on:

${n}^{2} + 9 n + 18 = 0$

To factor this, your basic problem is to find factors a and b such that:

a * b = 18 and a+b = 9

You might have to do a little trial and error to find these. After awhile, it becomes second nature. 6 and 3 fit the bill.

And this basically is all there is to it! You can write:

(n+6)(n+3) = 0

...which is true when n = -6 or n = -3.

GOOD LUCK