SOLUTION: Please help me on what is the difference between the below formulas: y1 - y2/x1 - x2 and y2 - y1/ x2 - x1 Ex. (4,9), (3,6) m = 5/2

Algebra ->  College  -> Linear Algebra -> SOLUTION: Please help me on what is the difference between the below formulas: y1 - y2/x1 - x2 and y2 - y1/ x2 - x1 Ex. (4,9), (3,6) m = 5/2      Log On


   



Question 52472: Please help me on what is the difference between the below formulas:
y1 - y2/x1 - x2 and y2 - y1/ x2 - x1
Ex. (4,9), (3,6) m = 5/2

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
First, you ought to use parentheses to make sure your problem is clearly understood:
(y1-y2)/(x1-x2) and (y2-y1)/(x2-x1)
These are the formulas for finding the slope (m) of a line that passes through two given points. While they may look a little different, both formulas will give you exactly the same result. Let's check using the two points in your problem:
(4, 9) and (3, 6)
%28y1-y2%29%2F%28x1-x2%29+=+%289-6%29%2F%284-3%29 = 3%2F1 = 3
%28y2-y1%29%2F%28x2-x1%29+=+%286-9%29%2F%283-4%29 = %28-3%29%2F%28-1%29+=+3%2F1 = 3