What are the coordinates of point g of the pre image

The image of the number line is missing, so i have attached it.

5 metres

Step-by-step explanation:

From the attached image, we can see that point A is at -2.5 while point B is at 2.5.

Thus,distance between points A and B is; 2.5 - (-2.5). Where -2.5 is the additive inverse of 2.5.

Minus outside bracket when multiplied by minus inside the bracket will yield a positive sign.. Thus: distance = 2.5 + 2.5 = 5 m