### Home > GB8I > Chapter 10 Unit 11 > Lesson INT1: 10.1.1 > Problem10-15

10-15.

Solve each of the following equations for the indicated variable.

1. Solve for $d$: $I = \frac { 3 } { 4 }md+18$

Start by subtracting $18$ from both sides.

2. Solve for $q$: $S = 25p + q$

$q = S − 25p$

3. Solve for $n$: $PV = nRT$

• To solve for $n$ you will need to divide both sides by $RT$.