Geometry Angles Quiz

Conditions for Parallel Lines

• If AB || CD || EF, then CE || DF.
• If l || m, then θ is unknown.
• If l || m and A || B, then θ is unknown.
• If QR || PS and PQ = QR, then θ is unknown.
• If l || m II n, then θ is unknown.

Angle Properties in Triangles

• In triangle ABC, if ∠A = 50° and the interior bisector of ∠B and ∠C intersects at point O, then ∠BOC is unknown.
• In triangle ABC, if ∠AOB = 125° and the interior bisector of ∠A and ∠B intersects at point O, then ∠ACB is unknown.
• In triangle ABC, if ∠A = 30° and the exterior bisector of ∠B and ∠C intersects at point O, then ∠BOC is unknown.
• In triangle ABC, if the interior bisector of ∠B and the exterior bisector of ∠C intersects at point O, and ∠A = 84°, then ∠BOC is unknown.

Length Properties in Triangles

• In triangle ABC, if AB = 6 cm, AC = 4 cm, and BC = 7 cm, then the length of BD is unknown where AD is the interior bisector of ∠A.
• In triangle ABC, if AB = 10 cm, AC = 14 cm, and BC = 6 cm, then the length of BD is unknown where AD is the interior bisector of ∠A.
• In triangle ABC, if AB = 5 cm, BC = 8 cm, and CA = 4 cm, then the lengths of AF, CE, and BD are unknown where AD, BE, and CF are the interior bisectors of ∠A, ∠B, and ∠C respectively.
• In triangle ABC, if AB = 10 cm, BC = 15 cm, ∠C = 30°, and ∠BDC = 130°, then the value of ∠ABC is unknown where D is a point on the side AC and AD : DC = 2 : 3.
• In triangle ABC, if AD is the exterior bisector of ∠A and AB = 6 cm, BC = 5 cm, and AC = 4 cm, then the length of CD is unknown.