∠A and ∠ � ∠B are complementary angles. If m ∠ � = ( 6 � + 2 ) ∘ m∠A=(6x+2) ∘ and m ∠ � = ( 4 � + 18 ) ∘ m∠B=(4x+18) ∘ , then find the measure of ∠ � ∠A.