In triangle ABC, angle A is 3 times and angle B is 5 times greater than angle C. Find all angles of triangle ABC.

Given:
ABC – triangle,
angle A = 3 * angle C,
angle B = 5 * angle C,
Find the degree measures of the angles of the triangle ABC: angle A, angle B, angle C -?
Decision:
Consider a triangle ABC.
Let the degree measure of angle C be equal to x °, then the degree measure of angle A is 3 * x °, and the degree measure of angle B is 5 * x °. We know that the sum of the degree measures of a triangle is 180 °. Let’s make the equation:
x + 3 * x + 5 * x = 180;
x * (1 + 3 + 5) = 180;
x * 9 = 180;
x = 180: 10;
x = 20 ° – angle С;
20 * 3 = 60 ° – angle A;
20 * 5 = 100 ° – angle B.
Answer: 20 °; 60 °; 100 °.