In triangle ABC, angle A is 50. The height BE and side BC form an angle of 20. Find the degree measure of the angle ACB.

Let us determine the degree value of the angle formed by the height BE and the side BA, knowing by the condition of the problem that the degree measure of the angle A is equal to 50 °, and also that the triangle ABE is rectangular:

180 – 90 – 50 = 40.

Let us determine the degree value of the angle B of the triangle ABC, knowing by the condition of the problem that the degree value of the angle formed by the height BE with the side BC is 20 °:

40 + 20 = 60.

Determine the degree value of the angle ACB of the triangle ABC:

180 – 50 – 60 = 70.

Answer: The degree value of the ACB angle is 70 °.