ΔABC and ΔDEF appear to be similar. Which set of measurements prove that the two triangles are similar?
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Answer:
C.
Step-by-step explanation:
Similar triangles have congruent corresponding angles, and proportional corresponding sides.
The only angle given is angle A, which will correspond to angle D if the similarity statement is true. That is, angle D must be 35°. (Eliminates choice D)
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The ratios of the given sides are AB:AC = 9:12 = 3:4. The corresponding sides would be DE:DF. (Eliminates choice A)
The remaining choices have side ratios of ...
B. DE : DF = 16 : 21 ≠ 3 : 4
C. DE : DF = 12 : 16 = 3 : 4
The set of measurements that would make ΔABC ~ ΔDEF is ...
DE = 12, DF = 16, and ∠D = 35°