Two cars leave an intersection. One car travels north; the other east. When the car traveling north had gone 15 mi, the distance between the cars was 5 mi more than the distance traveled by the car heading east. How far had the eastbound car traveled?

1 Answer
Sep 2, 2016

The eastbound car went 20 miles.

Explanation:

Draw a diagram, letting x be the distance covered by the car travelling eastbound.

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By pythagorean theorem (since the directions east and north make a right angle) we have:

15^2 + x^2 = (x+ 5)^2

225 + x^2 = x^2 + 10x+ 25

225 - 25 = 10x

200 = 10x

x = 20

Hence, the eastbound car has travelled 20 miles.

Hopefully this helps!