Given that < 1 and < 3 are corresponding angles with the same measure, and that < 1 and m < 38 ° are supplementary angles in which their measures add up to 180°:
Then:
m< 1 + m < 38° = 180°
m < 1 = 180° — m < 38°
m < 1 = 142°
Since m < 1 = m < 3, then m < 3 = 142°
