Question

1. What does the mark of the angles and sides of the triangle indicate?

Answer 1

2. You see them in your face:

$\displaystyle m∠F ≅ m∠C;$$\overline{FD}$ ≅ $\overline{CA}$

$m∠E ≅ m∠B;$$\overline{FE}$ ≅ $\overline{CB}$

$m∠D ≅ m∠A;$$\overline{ED}$ ≅ $\overline{BA}$

To sum up, corresponding parts of congruent triangles are always congruent [CPCTC].

1. The edge and angle markings of both triangles represent all corresponding parts. Each angle and edge corresponds with another angle and edge.

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