SOLUTION: (10, y) and (3,4): m=-2/7

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Question 1210214: (10, y) and (3,4): m=-2/7
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
(10, y) and (3,4): m=-2/7
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I will write in the same style as you write this post.
Hope you will understand everything. 

-2%2F7 = %28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29

-2%2F7 = %284-y%29%2F%283-10%29

-2%2F7 = %284-y%29%2F%28-7%29

It implies

2 = 4 - y

y = 4 - 2

y = 2.


ANSWER.  y = 2.

Solved to the end.



Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Informally, instead of using formal mathematics -- hoping it will help you understand the formal math....

The slope, "rise over run", is -2/7. That means that whenever x changes by 7 ("the run is 7"), y changes by -2 ("the rise is -2").

From (3,4) to (10,y), x changes by 10-3 = 7 (the run is 7), so the y should change by -2 (the rise is -2). A rise of -2 starting from y=4 puts you at y=2 (4 plus -2 equals 2).

ANSWER: 2