Subtraction of Integers

We will learn subtraction
of integers using number line.

We know that subtraction is the inverse of addition.
Therefore, to subtract an integer, we add its additive inverse.

For example, to
find +5 – (+2), we add +5 + (-2).

So, on the number line, we move to the left of +5 by 2 steps. +5 + (-2) = +3.

We know that to get a predecessor of a number we subtract 1.

So, predecessor of -20 is -20 – 1 = -21 and successor is -20 + 1 = -19

Solved examples on Subtraction of Integers:

1. Subtract +4 from +7.

Solution:

+7 – (+4) = +7 + (-4). So, we move 4 steps left to 7 on the
number line.

Hence, +7 + (-4) = 3.

2. Subtract (-3) from (-7).

Solution:

-7 – (-3) = -7 + (+3) = -4. So, we move 3 steps to the right of -7 on the number line.

Hence, (-3) from (-7) = -4.