19. Five mark exercise problems - I

A garden measuring 12 \(m\) by 16 \(m\) is to have a pedestrian pathway that is ‘\(w\)’ meters wide installed all the way around so that it increases the total area to 285 \(m^2\). What is the width \((w)\) of the pathway?

 

The width of the pathway \(=\)  \(m\).