How do you solve 8x + 3x = 121?

Feb 23, 2017

$x = 11$

Explanation:

Simplify the left side by collecting like terms.

$\Rightarrow 8 x + 3 x = 121$

$\Rightarrow 11 x = 121$

To solve for x, divide both sides of the equation by 11

$\frac{{\cancel{11}}^{1} x}{\cancel{11}} ^ 1 = \frac{121}{11}$

$\Rightarrow x = 11$

$\textcolor{b l u e}{\text{As a check}}$

Substitute this value into the left side and if equal to the right side then it is the solution.

$\left(8 \times 11\right) + \left(3 \times 11\right) = 88 + 33 = 121$

$\Rightarrow x = 11 \text{ is the solution}$