If m∠A = m∠B and m∠A + m∠C = m∠D, thenm∠B + m∠C = m∠D.
Answer
A
reflexive property
B
substitution property
C
symmetric property
D
transitive property
Explanation
Since m∠A = m∠B, we can replace m∠A with m∠B in the equation m∠A + m∠C = m∠D. This gives m∠B + m∠C = m∠D, so the statement uses the substitution property.
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