Question 185956: Could someone please help me find the equation of the line that goes through the points (-4,2) and (-3,-7). I am terrible at graphing and equations and in need of help. Thanks for your help in advance.
Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! Could someone please help me find the equation of the line that goes through the points (-4,2) and (-3,-7). I am terrible at graphing and equations and in need of help. Thanks for your help in advance.
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1st find the slope of the line thru the points.
Slope, m, is diff in y/diff in x
m = (-7-2)/(-3-(-4))
m = -9/1
m = -9
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Then, use this formula.
y-y1 = m*(x-x1) where (x1,y1) is either point.
y-2 = -9*(x+4)
y-2 = -9x-36
y = -9x - 34
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That always works. If you sub -4 for x, y = 2. Same for the other point.
Answer by stanbon(75887)  (Show Source):
You can put this solution on YOUR website! find the equation of the line that goes through the points (-4,2) and (-3,-7).
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Form: y = mx + b ; you need to find "m" and "b".
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m = slope = (-7-2)/(-3--4) = -9/1 = -9
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You now know m and you know y = 2 when x=-4 ;so solve for "b":
2 = -9*-4 + b
b = 2-36
b = -34
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Equation:
y = -9x - 34
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Cheers,
Stan H.
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