2. The addition property of equality.
Explanation
Step 1
[tex]\begin{gathered} 4x+7=10 \\ \text{Jenna added -7 ( or subtract 7) to both sides, so} \\ 4x+7-7=10-7 \\ 4x=3 \end{gathered}[/tex]she applied the addition property for inequalities. it states that if an inequality exists, adding or subtracting the same number on both sides does not change the inequality.
so, the answer is
2. The addition property of equality.