Answer: Choice C
Subtraction property of equality
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Explanation:
Let's say we started with the equation a = b
Subtract c from both sides to get a-c = b-c
This is the subtraction property of equality
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Example:
x+5 = 12
x+5-5 = 12-5 ... using the subtraction property of equality
x+0 = 7
x = 7
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For this current problem, we're subtracting 3 from both sides in the second step.
A very closely related property is the addition property of equality where we add the same thing to both sides.
Technically we could add -3 to both sides to get the same task done in the second step. But the subtraction property is more direct and straight-forward in my opinion.
