Question

Solve the equation.

$4.2x+6.4=40$

Short answer

The solution is $x=8$.

Step-by-step solution

Step 1- Consider the equation.

Consider the equation $4.2x+6.4=40$.

Subtract 40 from both sides of the equation.

Step 2- Step description.

$\begin{array}{l}4.2x+6.4=40\\ 4.2x+6.4-40=0\end{array}$

Step 3- Step description.

Simplify the equation as follows:

$\begin{array}{c}4.2x+6.4-40=0\\ 4.2x-33.6=0\\ 4.2x=33.6\end{array}$

Divide both sides of the equation by 4.2.

$\begin{array}{l}4.2x=33.6\\ x=\frac{33.6}{4.2}\\ x=8\end{array}$

Therefore, the solution is $x=8$.