How can you tell if three positive numbers form a pythagorean triple

The triangles are similar. what is the value of x? show your work.

Aiden drives to school and back each day. the school is 16 miles from his home. he averages 40 miles per hour on his way to school. if his trip takes 1 hour, at approximately what speed does aiden drive home?

In triangle opq right angled at p op=7cm,oq-pq=1 determine the values of sinq and cosq