SOLUTION: Find the equation of a line that goes through the points (-3, -5) and (-1, -2). Please help !

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Question 779662: Find the equation of a line that goes through the points (-3, -5) and (-1, -2).
Please help !
Answer by tutor_paul(519) About Me  (Show Source):
You can put this solution on YOUR website!
The equation of a line in slope/intercept form is:
y=mx%2Bb
Where m = slope, and b = y-intercept (the point at which the line crosses the Y-axis).
First, find the slope. Since you are given two points on the line, this is easy.
m=%28y2-y1%29%2F%28x2-x1%29
m=%28-2-%28-5%29%29%2F%28-1-%28-3%29%29
Watch your signs here!
m=3%2F2
So now you have the slope, and you are half done with the problem. To continue, just pick one of the given points (doesn't matter which one). Plug it into the equation for the line, and solve for b:
y=mx%2Bb
I am going to pick point (-3,-5):
-5=%283%2F2%29%28-3%29%2Bb
-5=-9%2F2%2Bb
b=9%2F2-5
b=-1%2F2
Now that you have the slope, and the y-intercept, just plug those in the the slope/intercept equation of the line, and you are done:
highlight%28y=%283x%2F2%29-1%2F2%29
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Good Luck,
tutor_paul@yahoo.com