SOLUTION: How would I find the slope of the line through points (15,1) and (4,2)?

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Question 120544: How would I find the slope of the line through points (15,1) and (4,2)?
Found 2 solutions by jim_thompson5910, solver91311:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Finding the slope


Slope of the line through the points (15, 1) and (4, 2)



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


m+=+%282+-+1%29%2F%284+-+15%29


m+=+%281%29%2F%28-11%29


m+=+-1%2F11



Answer: Slope is m+=+-1%2F11

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
Enter your coordinates into the two-point form of a line: y-y%5B1%5D=%28%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29%29%28x-x%5B1%5D%29.

It doesn't matter which of your points you call point 1 and which you call point 2 as long as you remain consistent while working the problem. Let's say (15,1) is point 1, and (4,2) is point 2.

y-1=%28%284-1%29%2F%282-15%29%29%28x-15%29

Then simplify and solve the equation for y. The slope will be the coefficient on the x term, because by solving for y you put the equation into the slope-intercept form, y=mx%2Bb

I'll leave the arithmetic to you. I'll also leave it as an exercise for the student to re-identify the points so that (4,2) is point 1, etc., and then prove that the resulting standard and slope-intercept forms of the equation are the same regardless of the order of the points.

Hope that helps,
John