# How do you solve 2x + 4x + 3x=21?

##### 1 Answer
Aug 3, 2015

I found $\frac{7}{3}$

#### Explanation:

You can add together all the terms on the left because they have the same litteral part and get:
$9 x = 21$
you can now transfer the $9$ to the right but dividing as:
$x = \frac{21}{9}$
This is because in your Equation the left has always to be equal to the right. If you decide to get rid of the $9$ on the left (dividing by $9$) you must do the same on the right:
$\frac{9 x}{\textcolor{red}{9}} = \frac{21}{\textcolor{red}{9}}$
$\frac{\cancel{9} x}{\cancel{9}} = \frac{21}{\textcolor{red}{9}}$
now you can divide both by $3$:
$x = \frac{\frac{21}{3}}{\frac{9}{3}} = \frac{7}{3}$