Angles D and G are both marked with double arcs, indicating they are congruent:
∠EGF ≅ ∠BDC
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<em>Other choices</em>:
BD is the short segment between the marked angles. It has no "decoration." EF is the longer segment with a single hash mark decoration. These are not corresponding parts, so are <em>not congruent</em>. There is no right angle in these triangles, so the <em>Pythagorean theorem is not applicable</em>.
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CD is the longest side, with no decoration. EF is the middle-length side with a single hash mark decoration. These are <em>not corresponding sides</em>.