Digital PSAT Math Practice Question 305: Answer and Explanation

Question: 305

Solve for x in the equation below:

7 + 2 (x - 3) = - 3 (x + 1) - 4

Correct Answer: A

Explanation:

(A) Start by distributing the 2 through the parentheses on the left and the 3 through the parentheses on the right:

\begin{array}{rcl} 7 + 2 (x - 3) & = & - 3 (x + 1) - 4 \\ 7 + 2 x - 6 & = & - 3 x - 3 - 4 \end{array}

Simplify and solve for x:

\begin{array}{rcl} 1 + 2 x & = & - 3 x - 7 \to \\ 5 x & = & - 8 \to \\ x & = & - \frac{8}{5} \end{array}