Exercise

The sum of two integers is $45.$ If one of them is $-23,$ the other is

The sum of $0$ and an integer is the same integer.

The expression $-9+11$ and $-11+9$ have the same value. 

$|8-5|=\left|8\right|+|-5|$

The sum of an integer and its opposite is a natural number. 

If $p$ and $q$ are two integers such that $p$ is the predecessor of $q$ then $p-q$ is equal to 

Find: $1-2+3-4+5-6+\dots \dots \dots +17-18+19-20.$

The construction dates of significant landmarks are given below. $AD$ is represented by positive integers and $BC$ by negative integers.

Write the following differences in ascending order. 

$(A-D), (C-B), (D-E), (C-D), (A-E)$