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GB-36-05-001 · Congruence proof

In triangles ABC and DEF, AB = DE = 9 cm, AC = DF = 18 cm and angle BAC = angle EDF = 122°. Prove that the triangles are congruent.

Congruent Triangles Booklet p. 90
Method
Check the 4 congruence rules (SSS, SAS, ASA, RHS): two equal sides and the included angle between them ⇒ SAS
Worked Example (GB-36-05-001)
1)
Two matching pairs of sides are equal.
2)
The equal angle lies between those sides, so SAS applies.
Ans = SAS congruence.