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How to write the equation of a line that passes through the points (-1,3) and (1,-1)

How to write the equation of a line that passes through the points (-1,3) and (1,-1)-example-1
User Praveenpds
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1 Answer

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Answer: y = -2x + 1

Solution:

To find the the equation use first find the slope using the equation:

m= y2-y1/x2-x1

m = -1-3/1-(-1)

m = -4/2

m = -2

Using the equation below,

y = mx + b

y = y coordinate

m = slope

x = x coordinate

b = y intercept

so to write the equation of line we need to find the y-intercept (b)

substitute the slope (-2) and any of the given pair of coordinates , right now i will be using (1,-1)

y = mx + b

-1 = (-2)(1) + b

-1+2 = b

1 = b

So the line of equation,

y = mx + b

y = -2x + 1






User Akos Nagy
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