Two vehicles, a car and a truck, leave an intersection at the same time. the car heads east at an average speed of 20 miles per hour, while the truck heads south at an average speed of 50 miles per hour. find an expression for their distance apart d (in miles) at the end of t hours.

Explanation:

Given:

't' hour be the time taken for travel by  both the vehicles and 'd'  be the distance between then

then

Distance traveled by the car = 20 × t miles

and

Distance traveled by the truck  = 50 × t miles

now, using the Pythagoras theorem

or

or

or

thus, the equation relating the distance 'd' with the time 't' comes as