We learnt how to add directed numbers in different situations and let us see how we can subtract directed numbers. We can subtract directed numbers like other actual numbers but there is a difference.

We all know that 5 subtracted by 3 is 2 but in directed numbers this is not the case.

5 - 3 = 2.

Worked Example

Let's say we do not have 5 pens and we have 3 pens so, let us subtract 3 pens from 5 pens and remember we said we indicate what we do not have with negative sign therefore, 5 pens that we do not have we write it as -5.

-5 - 3 = -8

How did we get -8 not -2 ?

To get -8 we should change the negative sign (-) between -5 and 3 replace it with plus sign (+) then put the negative sign on 3 to be negative 3 (-3).

So, we will have the following figure.

-5 + -3 = -8

Remember how we added directed numbers and above need as to go back and recall addition of directed numbers. But never write this figure just do it on your workings not on actual answer always write it this way -5 - 3 = -8.

What if we do not have 3 pens but we have 5 pens, how can we subtract 3 from 5? Remember for what we do not have we write -3 and for what we have we write 5.

Worked Example

Let subtract 5 from -3.

-3 - 5 = -8

How did we get negative eight (-8) ?

We replace minus sign (-) between -3 and 5 by plus sign (+) then put minus sign on 5 as negative 5 (-5).

So we have the following figure.

-3 + -5 = -8

This also makes us to recall how to add directed numbers. But make sure you do not write this figure in actual answer do it on your workings and always write it as -3 - 5 = -8.

We can always follow this procedure whenever we are subtracting directed numbers.