Question

даю 100 балов нужно сейчас

Answer 1

Пошаговое объяснение:

№1

-1 - 2 - 3 - (-4) - (-5) + (-4) + 6 + (-9) - 7 =

-1 - 2 - 3 + 4 + 5 - 4 + 6 - 9 - 7 =

(-1 - 2 - 3 - 4 - 9 - 7) + (4 + 5 + 6) =

-(1 + 2 + 3 + 4 + 9 + 7) + 15 =

-26 + 15 = -11

№2

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

-3 2/3 + 4 4/5 + 5 1/4 - 2 3/4 - 5/6 + 1/2 =

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

(-3 8/12 - 2 9/12 - 10/12) + (4 16/20 + 5 5/20 + 10/20) =

-(3 8/12 + 2 9/12 + 10/12) + 9 31/20 =

-5 27/12 + 10 11/20 = -7 3/12 + 10 11/20 =

-7 1/4 + 10 11/20 = -7 5/20 + 10 11/20 =

3 6/20 = 3 3/10