Answer:
The measures of angles A, B, and C are respectively 21°, 125°, and 34°
Explanation:
Equations
We are given some conditions applying to the internal angles on a triangle ABC.
The measure of angle A is 13 less than the measure of angle C.
The measure of angle B is 11 less than 4 times the measure of angle C
Let x = measure of angle C
The first conditions states:

The second conditions states:

The sum of all angles must be 180°, thus:

Simplifying:
6x -24 = 180
Adding 24:
6x = 204
Dividing by 6:
x = 204/6
x = 34



The measures of angles A, B, and C are respectively 21°, 125°, and 34°