Question from March SAT: Section 4 #33
In triangle ABC, angle A measures 48 degrees, angle B measures 88 degrees, and angle C measures 44 degrees. Triangle ABC is similar to triangle LMN, such that LM/AB = MN/BC = LN/AC = 3. What is the measure, in degrees, of angle L ?
When triangles are similar, their corresponding angles are congruent. Notationally, when we say triangle ABC is similar to triangle LMN, we list the corresponding angles in order, so A corresponds with L, B corresponds with M, and C corresponds with N. The question also reassures us of this by telling us which sides correspond–angle A will be across from BC, and angle L will be across from MN.
Long story short: because the question tells you that angle A measures 48°, and that triangles ABC and LMN are similar, you know that angle L also measures 48°.