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Question 1006236: Show the way using slope that the points (-6,5),(1,-2) and (3,-4) lie on a straight line.
please help me! Thanks it would be best if youll explain it. I will appreciate the help :)
Answer by rothauserc(4718)   (Show Source):
You can put this solution on YOUR website! show points (-6,5), (1,-2), (3, -4)
If these points lie on the same line, they will satisfy the equation for that line. To determine the equation, we will use the standard form of a line,
y = mx +b where m is the slope of the line and b is the y intercept
m = (y2 -y1) / (x2 -x1), we will pick the first two points to determine slope
m = (-2 -5) / (1 - (-6)) = -7/7 = -1, so far we have
y = -x + b
now use point 1 and substitute -6 for x and 5 for y
5 = -(-6) +b
5 = 6 + b
b = -1, therefore our equation is
y = -x -1
now check each point
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5 = -(-6) -1
5 = 5
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-2 = -1 -1
-2 = -2
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-4 = -3 -1
-4 = -4
***************
therefore the three points are on the same line y = -x -1
here is a graph of the line
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