Beginning Algebra With Applications, Chapter 2, 2.3, Section 2.3, Problem 82

Translate the phrase "the difference between fourteen times a number and the product of the number and seven" into a variable expression. Then simplify the expression.

$
\begin{equation}
\begin{aligned}
& \text{The unknown number: } n && \text{Assign a variable to one of the number quantities}\\
\\
& \text{Fourteen times the number: } 14n && \text{Use the assigned variable to write an expression for any other unknown quantity.}\\
\\
& \text{The product of the number and seven: } 7n && \text{Again, by using the assigned variable to write an expression for any other unknown quantity.}\\
\\
&= 14n - 7n && \text{Use the assigned variable to write the variable expression.}\\
\\
&= 7n
\end{aligned}
\end{equation}
$