# How do you evaluate 4a - 3a - a + a + 3a = 20?

Jan 11, 2018

$a = 5$

#### Explanation:

$\text{simplify the left side by collecting like terms}$

$\Rightarrow 4 a = 20$

$\text{divide both sides by 4}$

$\frac{\cancel{4} a}{\cancel{4}} = \frac{20}{4}$

$\Rightarrow a = 5 \text{ is the solution}$

Jan 11, 2018

$a = 5$

#### Explanation:

$4 a - 3 a - a + a + 3 a = 20$

You have $a$ common in every term:

$a \left(4 - 3 - 1 + 1 + 3\right) = 20$

Do the operations and you are left with

$4 a = 20$

$a = \frac{20}{4}$

$a = 5$

Jan 11, 2018

$a = 5$

#### Explanation:

$4 a - 3 a - a + a + 3 a = 20$

First bring all the positive terms together and negative terms together

$4 a + a + 3 a - 3 a - a = 20$

Now all the terms are like terms, so add them keeping the sign same

$8 a - 4 a = 20$

Now subtract the terms

$4 a = 20$

Now divide the equation by $4$ on both sides. We get,

$a = 5$

Hope it helped you!