Реши уравнения:

а) 2 5/6 - (-у+7) = - 8 1/2

2 5/6 - (-у+7) = - 8 1/2

2 5/6+у-7=-8 1/2

2 5/6+у-6 6/6=-8 1/2

-4 1/6+у=-8 1/2

у=-8 1/2+4 1/6 - 8 1/2+4 1/6=-8 3/6+4 1/6=-4 2/6=-4 1/3

у=-4 1/3

проверка 2 5/6 - ( - (-4 1/3) + 7) = - 8 1/2

2 5/6 - (4 1/3+7) = - 8 1/2

2 5/6-11 1/3=-8 1/2

2 5/6-10 4/3=-8 1/2

2 5/6-10 8/6=-8 1/2

-8 3/6=-8 1/2

-8 1/2=-8 1/2