Complementary angles add up to 90 degrees and supplementary angles add up to 180. Straight lines such as the x-axis equate to 180. This is why angle 37 degrees is a supplementary angle because it lies as an angle on the x-axis specifically. However, the angle 63 degrees is complementary because it splits one of the quadrants. One quadrant equates to 90 degrees which is why the angle 63 degrees is complementary.
