SOLUTION: Write an equation for the line that passes through (-2,1) and (7,-3)

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Question 160155: Write an equation for the line that passes through (-2,1) and (7,-3)
Found 2 solutions by KnightOwlTutor, nabla:
Answer by KnightOwlTutor(293) (Show Source):
You can put this solution on YOUR website!
First we have to find the slope of the line m=y2-y1/x2-x1=rise/run
-3-1/7-(-2)=-4/9
y=-4/9x+b
plug in the x and y values of one point(-2,1) to determine the value of b the constant.

1=(-4)(-2)/9+b
9/9=8/9+b
Subtract 8/9 from both sides

1/9=b
Let's confirm that it is correct by
plugging in the x,y values of the second point and see if we are correct
y=-4/9x+1/9
(7,-3)
-3=-4(7)/9+1/9
-3=-28/9+1/9
-3=-27/9

Answer by nabla(475) (Show Source):
You can put this solution on YOUR website!
[1] Find the slope of the line connecting the two points. m=(y2-y1)/(x2-x1)=(-3-1)/(7-(-2))=-4/9.
[2] Use point slope form of a line with one point: y-y1=m(x-x1).
y-1=(-4/9)(x-(-2))
y=(-4/9)x+1/9