(d)
From part (a) we can conclude:
The angles in △ABC have the same measures as the angles in △DEF
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From part (b) we can conclude:
The ratios of corresponding side lengths are not all equal to each other.
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If two angles of one triangle are congruent to two angles of another triangle, the triangles are similar by Angle-Angle (AA) Similarity
Therefore:
The triangles are similar
