# How do you solve 15= - 11d - 18?

Mar 14, 2017

$d = - 3$

#### Explanation:

Isolate the $- 11 d$. To do that, you move the constants ALL to one side of the equation.

So in this case, you would have to add $18$ to BOTH sides of the equation to balance it on both sides.

If you don't then, the equation would be unbalanced and you ONLY make your life harder and the equation would be impossible to solve.

After you have added $18$ to BOTH sides, you will get

$15 + 18 = - 11 d - \cancel{18} + \cancel{18}$

$33 = - 11 d$

You isolated the $- 11 d$ because you want to solve for $d$.

Do that, you would like to divide $- 11$ on BOTH SIDES to keep the equation balanced for the same reason as above.

REMEMBER, NOT TO LOSE THE NEGATIVE SIGN DURING YOUR CALCULATIONS BECAUSE THEN YOU WOULD CHANGE THE ENTIRE PROBLEM.

After that, you will get to the final answer

$\frac{33}{- 11} = \frac{\cancel{- 11} d}{\cancel{- 11}}$

$d = - 3$