Find the size of the boundary angles if one angle is 5 times the other.

Judging by the condition of the assignment, it deals with adjacent corners. Then it makes sense to remember that the sum of adjacent angles is always 180o.

Let the smaller of the angles be equal to x o. Then, in accordance with the condition of this task, the larger of the angles can be designated as (5 * x) o. Therefore, taking into account the property of adjacent angles indicated above, the following equation can be drawn up:

x + 5 * x = 180.

Let’s solve the equation:

x + 5 * x = 180;

6 * x = 180;

x = 180: 6;

x = 30 o.

Then the 2nd angle is:

30 * 5 = 150 o.