Hello, Errisa!

The problem has a strange answer . . .

A north-south highway intersects an east-west highway at point P.

A car crosses P at 10:00 am, traveling east at a constant speed of 20 km/hr.

A car north of P, twenty minutes later passes that same point, traveling south at 60 km/hr.

Find the approximate the minimum distance between the automobiles.

Answer: 6.3 km

At 10:00, car drives east from at 20 km/hr.Code:| | 20/3 Q 20t R P o - - - o - - - - o | * | * 60t | * x | * | * S o

By 10:20, it has moved to point km.

In the next hours, it has moved km to point

In the same hours, car moves from to at 60 km/hr.

. .

Let = distance between the cars,

Pythagorus: .

To minimize , set and solve.

We have: .

Negative time?

. . . The minimum distance occured two minutes10:20.before

At 10:18, car was 6 miles east of point

At 10:18, car was 2 milesof pointnorth

Their distance was: .