Answer:
D. Subtraction property of equality.
Explanation:
We have been given an equation
. We are asked the property used in the second step of equation to solve it.
Step 1:
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Step 2:
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We can see that
is subtracted from both sides of equation.
We know that subtracting same quantity from both sides of equation is known as subtraction property of equality.
Therefore, option D is the correct choice.