15. Five mark exercise problem VI

Two trains leave a railway station at the same time. The first train travels due west and the second train due north. The first train travels at a speed of \(20 \ km/hr\) and the second train travels at \(30 \ km/hr\). After \(2\) hours, what is the distance between them?

 

The distance between the two trains is $i\overline{)i}$ \(km\).