Ответ:

В решении.

Пошаговое объяснение:

1.

а) -5/13 + (-7/13) =

= -(5/13 + 7/13) =

= -12/13;

б) 3/11 + (-8/11) =

= 3/11 - 8/11 =

= -(8/11 - 3/11) =

= -5/11;

в) -9/17 + 13/17 =

= +(13/17 - 9/17) =

= 4/17.

2.

а) -2/5 + (-2/15) =

= -(2/5 + 2/15) =

общий знаменатель 15:

= -(3*2 + 2)/15 =

= - 8/15;

б) -2/5 + 3/4 =

= -0,4 + 0,75 =

= +(0,75 - 0,4) =

= 0,35;

в) -11/27 + 5/18=

общий знаменатель 54:

= (-11*2 + 3*5)/54 =

=(-22 + 15)/54 =

= -7/54.

1.

а) -4/11 - 6/11 =

= -(4/11 + 6/11) =

= -10/11;

б) 5/13 - 8/13 =

= -(8/13 - 5/13) =

= -3/13;

в) -8/17 - (-12/17) =

= -8/17 + 12/17 =

= +(12/17 - 8/17) =

= 4/17.

2.

а) -1/4 - 3/16 =

= -(1/4 + 3/16) =

общий знаменатель 16:

= -(4*1 + 3)/16 =

= -7/16;

б) -1/4 - (-2/5) =

= -1/4 + 2/5 =

= -0,25 + 0,4 =

= 0,4 - 0,25 = 0,15;

в) -5/36 - (-5/27) =

= -5/36 + 5/27 =

общий знаменатель 108:

=(-5*3 + 4*5)/108 =

= (-15 + 20)/108 =

= 5/108.