SOLUTION: Find the equation for the line that passes through the indicated pair of points. (9,-8) and (7,-4)

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Question 5877: Find the equation for the line that passes through the indicated pair of points.
(9,-8) and (7,-4)
Found 2 solutions by Abbey, ichudov:
Answer by Abbey(339) About Me  (Show Source):
You can put this solution on YOUR website!
first find the slope:
%28y-y1%29%2F%28x-x1%29
%28-8-%28-4%29%29%2F%289-7%29
-4%2F2
slope = -2
Then use y=mx+b and substitute one set of points into the equation:
-8=-2(9)+b
-8=-18+b
b=10
so the equation is y=-2x+10

Answer by ichudov(507) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: FIND EQUATION of straight line given 2 points
hahaWe are trying to find equation of form y=ax+b, where a is slope, and b is intercept, which passes through points (x1, y1) = (9, -8) and (x2, y2) = (7, -4).
Slope a is a+=+%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29+=+%28-4--8%29%2F%287-9%29+=+-2.
Intercept is found from equation a%2Ax%5B1%5D%2Bb+=+y%5B1%5D, or -2%2A9+%2Bb+=+10. From that,
intercept b is b=y%5B1%5D-a%2Ax%5B1%5D, or b=-8--2%2A9+=+10.

y=(-2)x + (10)

Your graph: