IMO Practice Test — Angles in Parallel Lines & Triangles

In triangle ABC, angle A = 50 degrees and angle B = 70 degrees. Find the exterior angle at vertex C.

In a parallelogram, one angle is 65 degrees. Find the largest angle.

Two parallel lines cut by a transversal. One angle = (7x-20) degrees and its corresponding angle = (3x+60) degrees. Find x.

Triangle PQR has angles 2x, 3x, and 5x degrees. Classify the triangle by its angles.

The exterior angle at vertex A of triangle ABC is 150 degrees. If angle B : angle C = 2:3, find angle B.

Two parallel lines L1 and L2 are cut by a transversal. One angle at L1 is 70 degrees. Find the consecutive interior angle at L2.