- 7 1/2-(x+ 3 2/7)=10 5/14 10баллов
-7 1/2 - (х + 3 2/7) = 10 5/14 -7 1/2 - 10 5/14 = х + 3 2/7 -17 12/14 = х + 3 2/7 х = -17 12/14 - 3 2/7 х = -20 16/14 = - 21 2/14 = -21 1/7
спасибо)