Answer:
140°
Step-by-step explanation:
Two angles are supplementary if they add up to 180 degrees.
Since ∠A and ∠B are supplementary angles.
m∠A+m∠B=180°
(5x + 25)°+(x + 17)°=180°
5x+x+25+17=180
6x+42=180
6x=180-42
6x=138
x=138/6
x=23
Therefore, the measure of angle A will be:
m∠A=(5x + 25)°
=5(23)+25
=115+25
=140°
The measure of angle A is 140 degrees.