Explanation:
The sum of measure of supplementary angles = 180°
The measure of angle 1 is given as 10x + 5 and the measure of angle 2 is given as 6x - 1
10x + 5 + 6x - 1 = 180 add like terms
16x + 4 = 180 subtract 4 from both sides
16x = 176 divide both sides by 16
x = 11
To find the measure of each angle, relace x with 11
angle 1,
10*11 + 5 = 115
angle 2,
6*11 - 1 = 65