A ∠A and ∠ B ∠B are supplementary angles. If m ∠ A = ( 8 x − 25 ) ∘ ∠A=(8x−25) ∘ and m ∠ B = ( 7 x − 5 ) ∘ ∠B=(7x−5) ∘ , then find the measure of ∠ B ∠B.