Question

twice a number plus four equals 22 .what is the number ?

Answer 1

Let's call x to the unknown number.

"Twice a number" means we need to multiply the unknown number by 2, that is, 2x.

Then, "twice a number plus four equals 22" is represented by the next equation:

$2x+4=22$

Subtracting 4 at both sides of the equation:

$\begin{gathered} 2x+4-4=22-4 \\ 2x=18 \end{gathered}$

Dividing by 2 at both sides of the equation:

$\begin{gathered} \frac{2x}{2}=\frac{18}{2} \\ x=9 \end{gathered}$

The number is 9