Question

What mistake did the student make when solvingtheir two-step equation?(a)(b)If correctly solved what should the value of x be?

Answer 1

Given

$4-2x=-2$

Part A

The first thing is to subtract 4 from both sides, it should not add...

The mistake the student made was he or she added 4 to both sides instead of subtracting 4 from both sides.

$\begin{gathered} 4-4-2x=-2-4 \\ -2x=-6 \end{gathered}$

Part B

$\begin{gathered} \text{Divide both sides by -2} \\ -\frac{2x}{-2}=-\frac{6}{-2} \\ \\ x=3 \end{gathered}$