Math question: Prove that if two triangles have two sides and the included angle of one equal respectively to two sides and the included angle of the other, then they are congruent.
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What is the result of multiplying a vector with magnitude 3 and direction 30 degrees by a vector with magnitude 5 and direction 120 degrees?
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Math question: In ΔABC, if AB ≅ AC and ∠B ≅ ∠C, which congruence rule can be used to prove ΔABC ≅ Δ