Complementary angles always are 90 degrees when added to each other, so:
x = angle 1
x + 89.8 = angle 2
x + x + 89.8 = 90
2x = 90 - 89.8
2x = 0.2
x = 0.1
angle 1 = 0.1 degrees
angle 2 = 0.1 + 89.8 = 89.9 degrees
if you want to check, just sum one to the other and see if they equal 90, like this: 89.9 + 0.1 = 90
