The bisector AL is drawn in triangle ABC, angle ALC is 37 °, angle ABC is 25 °. Find the ACB angle.

Given:
triangle ABC,
AL – bisector,
angle ALC = 37 degrees,
the angle ABC is 25 degrees.
Find the degree measure of the angle ACB -?
Decision:
Consider a triangle ABC. If AL is a bisector, then the angle BAL = angle ALC = 37 degrees. So angle A = angle BAL = angle ALC = 37 + 37 = 74 (degrees).
Knowing that the sum of the degree measures of any triangle is 180 degrees, that is
angle A + angle B + angle C = 180 degrees;
angle C = 180 – angle A – angle B;
angle C = 180 – 74 – 25;
angle C = 81 degrees;
angle C = angle ACB = 81 degrees.
Answer: 81 degrees.