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I suspect that your question should be formulated differently :
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| How far will be one car from another in 20 minutes ? |
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If so, then you have a right angled triangle.
Its legs are = 15 miles and
= 20 hours,
and "how far" is then the hypotenuse of this right angled triangle.
So, the distance is = = = 25 miles.
Notice that the triangle is, actually, (3,4,5)-triangle with the legs 15 and 20 miles,
so you can get the answer of 25 miles practically MENTALLY.
Two cars leave the same point. One travels north at 45 mph and the other travels east at 60 mph. How many miles will each other be within 20 minutes?
The scenario represents a right-triangle, with the distance each had traveled after 20 minutes being the legs of the right-triangle, while the distance between them
after 20 minutes represents the hypotenuse of the right-triangle
After the slower car had traveled for 20 minutes, it’d covered
After the faster car had traveled for 20 minutes, it’d covered
We then have a right-triangle with legs 15 and 20, and the hypotenuse is needed. The legs being 15 and 20 represent a 3-4-5 PYTHAG TRIPLE, TIMES 5, or a
3(5)-4(5)-5(5) = 15-20-25 PYTHAG TRIPLE. Therefore, hypotenuse or distance between the 2 cars, after = .