In a triangle, the first angle is 2 times the second and 20 degrees less than the third. Find the large corner of the triangle.

1. Suppose that the degree measure of the first angle is x. Based on the condition, we express the second angle through the unknown x, that is, as x / 2. Similarly, we will express the third angle as (x + 20). By the theorem on the sum of the angles of a triangle, the sum of the sides of a triangle is 180 degrees. Let’s compose and solve the equation:

x + x / 2 + (x + 20) = 180;

x + x / 2 + x + 20 = 180;

2x + x / 2 = 160;

4x / 2 + x / 2 = 160;

5x / 2 = 160;

5x = 320;

x = 64.

2. Find a larger angle:

64 + 20 = 84.

Answer: The large angle of the triangle is 84 degrees.