Respuesta :

First student has a 1 minute head start at .20 miles per minute.
This is a distance of .2 miles.
The second student has to make up this distance by running at .25 miles per minute.  This produces a net gain on the first student by
(.25 -.20) = .05 miles per minute.

So how long does it take to run .20 miles at .05 miles per hour?
.2 miles / .05 miles per minute = 4 minutes.


1)
Linear form:

y = .20x +.20

y = .25x - .25

Standard form:

.20x - y = -.20

-.25x + y = -.25

Finding their solution:

-.05x = -.45

x = 9

Answer:

The answer is it will take 9 minutes for the second runner to catch up with the first runner.

2)
72x + 436 = -96x + 1108

72x = -96x + 672

168x = 672

x = 4

Answer:

x = 4