(A) The ratios of corresponding sides of triangles XYZ and X'Y'Z' are equal.
No matter what you dilate it to, the sides, when simplified, must be the same. For example:
ΔABC has sides 1, 1, √2
After dilating by 5
ΔA'B'C' has sides (1 x 5), (1 x 5), (√2 x 5)
ΔA'B'C' side's will equal, 5, 5, 5√2
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(A) The ratios of corresponding sides of triangles XYZ and X'Y'Z' are equal.
should be your answer
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hope this helps