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-   -   D=RT (Distance = Rate x Time) (http://mymathforum.com/algebra/13714-d-rt-distance-rate-x-time.html)

 Mighty Mouse Jr July 9th, 2010 04:31 PM

D=RT (Distance = Rate x Time)

[color=#FF0000]Here is the problem:[/color]

Two birds start flying from the tops of two towers 50 ft apart at the same time and at the same rate. One tower is 30 ft high, and the other tower is 40 ft high. The birds reach a grass seed on the ground at exactly the same time. How far is the grass seed from the 40 foot tower?

[color=#FF0000]I have absolutely no clue how to set up an equation for this problem. Can you please explain the equation you provide.[/color]

 skipjack July 9th, 2010 05:31 PM

If the seed lies directly between the towers and is x ft from the 40 ft tower and (50 - x) ft form the 30 ft tower, and if each bird flies in a straight line to the seed, each flies the same distance. Using Pythagoras to give two expressions for the square of that distance you get the equation below.

(50 - x)² + 30² = x² + 40²

 Mighty Mouse Jr July 9th, 2010 06:18 PM

Re: D=RT (Distance = Rate x Time)

The book said the answer is 18 ft. The grass seed is 18 ft from the 40-foot tower. I don't think your equation provides the same answer; But I think you still have to use the Pythagorean Theorem.

 MarkFL July 9th, 2010 06:29 PM

Re: D=RT (Distance = Rate x Time)

Quote:
 Originally Posted by Mighty Mouse Jr ...I don't think your equation provides the same answer...
18 is indeed a solution of the equation skipjack provided.

 Mighty Mouse Jr July 9th, 2010 06:47 PM

Re: D=RT (Distance = Rate x Time)

Disregard what I just said about your equation being incorrect. It is correct; It was an error on my part.

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