Question 1178426
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Let the faster train's speed be represented by *[tex \Large r].  Then the slower train's speed must be *[tex \Large r\ -\ 4].


Furthermore, because distance is equal to rate times time, the distances traveled by the two trains in two hours are *[tex \Large 2r] and *[tex \Large 2(r\,-\,4)].


Since the trains are traveling at right angles to each other, these two distances are the legs of a right triangle where we are given that the hypotenuse measures 42.80 miles.


Using the Pythagorean Theorem:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ \(2r\)^2\ +\ \(2(r\,-\,4)\)^2\ =\ 42.80^2]


Simplify and solve the quadratic for *[tex \Large r], remembering to round to the nearest integer when all of your calculations are complete.

																
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> 
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