Complementary angles by definition sum up to 90 degrees.
Let x = measure of angle2.
It's given that angle1 = x + 54
Since complementary, we know (x+54)+x = 90
2x+54=90
2x=36
x=18.
So angle2 measures 18 degrees and angle1 is 18 degrees+54 degrees, or 72 degrees. 72+18 = 90 as expected for complementary angles.