Tommy and zach are starting out at the same position. tommy runs north at 3 miles per hour and zach starts to run east 2 hours later at the rate of 4 miles per hour. how long until tommy and zach are 8 miles apart?

hours.

Step-by-step explanation:

We know that,

Distance = speed × time

Given,

Speed of tommy = 3 miles per hour,

So, the distance covered by him 2 hours = 6 miles,

Also, speed of Zach = 4 miles per hour,

Let after x hours they are 8 miles apart,

That is, total distance covered by Tommy = 6 + 3x,

And, total distance covered by Zach = 4x,

Thus, by making the diagram of this situation,

We get,

A right triangle having hypotenuse 8 and legs 3x+6 and 4x,

By the pythagorean theorem,

⇒ x = or x = -2

Number of hours can not be negative,

Hence, after hours they are 8 miles apart.

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