The outer corner of a triangle is 140, and the non-adjacent inner angles are 3: 4. find the corners of the triangle.

This problem can be solved using the equation:
Let x be one piece, then the first angle of the triangle is 3x and the second angle is 4x. Since the value of the external angle of a triangle is equal to the sum of two internal angles of a given triangle, not adjacent to it, and we know that it is equal to 140 °, we have the following equation:
3x + 4x = 140;
7x = 140;
x = 140: 7;
x = 20 ° – one part;
20 * 3 = 60 ° – the value of the first angle;
20 * 4 = 80 ° – the magnitude of the second hum;
Now let’s find the third corner:
180 – 60 – 80 = 40 °;
Answer: 40 °, 60 °, 80 °.