12+-13

Replace all occurrences of +- with a single -. A plus sign followed by a minus sign has the same mathematical meaning as a single minus sign because 1⋅-1=-1

12-13

To write 12 as a fraction with a common denominator, multiply by 33.

12⋅33-13

To write -13 as a fraction with a common denominator, multiply by 22.

12⋅33-13⋅22

Multiply 12 and 33.

32⋅3-13⋅22

Multiply 2 by 3.

36-13⋅22

Multiply 13 and 22.

36-23⋅2

Multiply 3 by 2.

36-26

36-26

Combine the numerators over the common denominator.

3-26

Subtract 2 from 3.

16

The result can be shown in multiple forms.

Exact Form:

16

Decimal Form:

0.16‾

Add 1/2+-1/3