Answer: the angles are 65 degrees and 115 degrees.
Explanation:
Let x represent the number.
An angle measures 17 more than 3 times a number. This means that the angle is
3x + 17
A second angle is three more than 7 times the same number. This means that the second angle is
7x + 3
If two angles are supplementary, it means that their sum is 180 degrees. Therefore,
3x + 17 + 7x + 3 = 180
3x + 7x + 17 + 3 = 180
10x + 20 = 180
10x = 180 - 20
10x = 160
x = 160/10
x = 16
The first angle is
3 × 16 + 17 = 48 + 17 = 65 degrees
The second angle is
7 × 16 + 3 = 112 + 3 = 115 degrees