# How do you check that the solution is 9 for the equation 3(x - 1) - 2(x + 3) = 0?

Sep 28, 2014

$3 \left(x - 1\right) - 2 \left(x + 3\right) = 0$

Distribute the $3$ and the $- 2$

$3 \cdot x - 3 \cdot 1 - 2 \cdot x - 2 \cdot 3 = 0$

$3 x - 3 - 2 x - 6 = 0$

Group the like terms

$3 x - 2 x - 3 - 6 = 0$

Combine the like terms

$x - 9 = 0$

adding $9$ on both sides to get value of $x$ ;

$x - 9 + 9 = 0 + 9$

$x = 9$

In order to check if $9$ is the correct answer , substitute $9$ as value of $x$ in the above equation;

$3 \left(x - 1\right) - 2 \left(x + 3\right) = 0$

$3 \left(9 - 1\right) - 2 \left(9 + 3\right) = 0$

$3 \left(8\right) - 2 \left(12\right) = 0$

$24 - 24 = 0$ ( Proved)