Fill in the blanks:

___ – 15 = –10

The above equation can be interpreted as follows:

We need to subtract 15 from a number so that we get (-10).
(0.5 mark)

Now, if we consider the number line, we need to go 15 units to the left of a number to reach (-10).
(0.5 mark)

We can reach that number by going to the right of (-10) by 15 units on the number line.

Hence, we get 5.

$\underset{–}{5}$ – 15 = –10
(1 mark)