Question

∠1 is a complement of ∠4, and m∠1=33∘m. Find m∠4.

Answer 1

Complementary angles equal 90°.

This means that if ∠1 is complementary to ∠4, then 
∠1 + ∠4 = 90°

33 + x = 90
x = 57

m∠4 = 57°

Answer 2

complement , sum = 90
m∠1=33∘
then m<4 = 90 - 33 = 57

answer
m<4 = 57