# How do you simplify \frac { 3a } { 2a b } - \frac { 2a } { 4}?

Aug 23, 2017

$\frac{a \left(3 - a b\right)}{2 b}$

#### Explanation:

First, you make a common denominator.

$\frac{3 a}{2 a b} - \frac{2 a}{4} = \frac{3 a}{2 a b} - \frac{2 \cdot {a}^{2} \cdot b}{4 a b}$

Next, you multiply the fraction $\frac{3 a}{2 a b}$ in the numerator and denominator by $2$. Then you get

$\frac{6 a}{4 a b}$

Now you do

$\frac{6 a}{4 a b} - \frac{2 \cdot {a}^{2} \cdot b}{4 a b} = \frac{2 a \left(3 - a b\right)}{4 b} = \frac{a \left(3 - a b\right)}{2 b}$

Sorry for making it so complicated.