The number line shows numbers graded into three parts each such that each point between numbers represent 0.33 units.
This means the red line moving towards the left is a negative because it falls to the left of point 0, where the division between positive and negative numbers take place.
Hence the red line indicates -3.33
The blue line is movin towards the right which means its a positive value. Note that it begins from -3.33 and ends at -1.33. Hence the blue line is a positive value and it covers two units.
The equation that models this number line can be written out as
