Well, you know the m in y=mx+b is the slope of a linear line. In order to find slope, m, we can use the formula m= y2-y1/x2-x1, where x1,x2,y1,y2 are x points and y points in a line, so we have m= -3+8/2-4 = -5/2
To solve for b, we choose a point on the line, say, (4,-8), and plug it into the y=mx+b equation, so we get
-8=(-5/2)4+b
-8=-10+b
b=2
So our equation for the line is
[Answer: (5/2)x + y = 2] or
[Answer: 5x + 2y = 4] (multiply everything in the answer above by 2)
2007-12-31 07:41:12
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answer #1
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answered by ¿ /\/ 馬 ? 7
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well... lets take a crack at it..
firstly we find the slope of the equation, passing through both points.
so that we get m = (-3+8)/(2-4) = - 5/2
secondly we use the point slope formula
namely y-y1= m(x-x1).. where here, (x1, and y1) are a point chosen from the two given.. lets choose (4,-8)..
to get y+8 = -5/2 (x-4).. from which you can put into the Standard form
Ax +By = C..
which you can do!!... hope that helps..
2007-12-31 15:48:22
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answer #2
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answered by JAC 3
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Let's choose a point and calculate slope in one equation as follows:
(y+3) / (x-2) = (-3-(-8)) / (2-4)
(y+3) / (x-2) = 5/(-2)
Cross multiplying and simplifying gives
y = -5/2(x) + 2
2007-12-31 15:46:53
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answer #3
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answered by stanschim 7
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Vector thas passes through the points:
(4, -8) - (2, -3)
V = (2, -5)
Continuous form:
(x - xo) / vx = (y - yo) / vy
(x - 2) / 2 = (y - (-3)) / (-5)
-5 * (x - 2) = 2 ( y + 3)
-5x + 10 = 2y + 6
-5x - 2y + 4 = 0
5x + 2y - 4 = 0
Bye and happy new year
2007-12-31 15:46:04
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answer #4
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answered by Anonymous
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