Beginning Algebra With Applications, Chapter 2, Review Exercises, Section Review Exercises, Problem 16

Simplify $2x + 3[4 - (3x - 7)]$

$
\begin{equation}
\begin{aligned}
&= 2x +3 [4 + (-1)(3x) - (-1)(7)] && \text{Use the Distributive Property}\\
\\
&= 2x + 3 [ 4 - (1 \cdot 3) x + (1) (7)] && \text{Use the Associative Property of Multiplication to group factors}\\
\\
&= 2x + 3[ 4- 3x + 7] && \text{Evaluate}\\
\\
&= 2x +3 [11-3x] && \text{Add terms}\\
\\
&= 2x + 3(11) - 3(3x) && \text{Again, by using the Distributive Property}\\
\\
&= 2x + 3(11) - (3 \cdot 3) x && \text{Use the Associative Property of Multiplication to group factors}\\
\\
&= 2x + 33 - 9x && \text{Evaluate}\\
\\
&= 33 - 7x && \text{Combine like terms}
\end{aligned}
\end{equation}
$