-- The trains start moving at the same time.
-- The space between them is initially 252.5 miles.
-- They reduce the distance between them at the rate of (124.7+253.5)=378.2mph.
-- It will take them (252.5 / 378.2) = 0.6676 hour to meet.
That's 40min 3.49sec .
-- After tooting and puffing toward each other for 8 minutes, they still have <em>32min 3.49sec</em> to go before they meet each other. We're all hoping that they're on different tracks.
Answer:
b
Step-by-step explanation:
Answer:
the answer is B
Step-by-step explanation:
i just took the test, hope this can help?
It is convenient to do part b first, then use that result to do part a.
b. For some pair of points (x1, y1) and (x2, y2), you want to find a point (a, b) such that (a, b) - (x1, y1) = (x2, y2) - (a, b). That is, the differences of coordinates from one end to the center are the same as the differences from the center to the other end.
Adding (a, b) to the above equation gives
2(a, b) - (x1, y1) = (x2, y2)
Adding (x1, y1) then gives
2(a, b) = (x1, y1) + (x2, y2)
Finally, dividing by 2 gives a formula for (a, b):
(a, b) = ((x1, y1) + (x2, y2))/2
The midpoint is the average of the end points.
a. Using the result from part b, the midpoint is
midpoint = ((2, 3) + (6, 7))/2 = (8, 10)/2
midpoint = (4, 5)
