Ages 12–14🧮 Mathematics10 verified questions on this shelf

Angles in triangles (age 12+)

Know and use the criteria for triangle congruence (SSS, SAS, ASA, RHS), use standard labelling conventions for sides and angles of triangle ABC, and determine whether two triangles are congruent

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Question 1 of 3

Triangles ABC and DEF have the following measurements: AB = 6 cm, BC = 9 cm, AC = 12 cm; DE = 6 cm, EF = 9 cm, DF = 12 cm. Which triangle congruence criterion can be used to prove △ABC≅△DEF\triangle ABC \cong \triangle DEF?

Question 2 of 3

Triangle ABC has side lengths AB = 9 cm, BC = 7 cm, AC = 5 cm. Triangle DEF has side lengths DE = 5 cm, EF = 7 cm, DF = 9 cm, and we also know that ∠A = ∠D = 60°. Which of the following statements correctly writes the congruence of the two triangles with the proper matching of corresponding vertices?

Question 3 of 3

Triangle XYZ has side XY = 7 cm, side YZ = 5 cm, and angle ∠XYZ = 60°. Triangle PQR has side PQ = 7 cm, side QR = 5 cm, and angle ∠PQR = 60°. Which triangle congruence criterion can be used to prove that △XYZ ≅ △PQR?

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