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Write the equation of a line in slope intercept form that passes through the two points. 4,-1 and 6,-7

User Eeva
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1 Answer

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10 votes

A line has an equation of,


y=mx+n.

m is called a slope

n is called y-intercept

We are also given two points
(x_1,y_1)=(4,-1),(x_2,y_2)=(6,-7).

We begin with computing the slope,


m=(\Delta y)/(\Delta x)=(y_2-y_1)/(x_2-x_1)=(-7-(-1))/(6-4)=(-7+1)/(2)=(-6)/(2)=\boxed{-3}

We have computed the slope m and our equation is almost done,


y=-3x+n

Next step is to find out what y-intercept n is. I will use point
(4,-1) and insert x and y it into already known equation, then solve for n,


-1=-3(4)+n


-1=-12+n\implies n=\boxed{11}

The reason I can insert coordinates of a point as x and y is because this particular point is in the line described by equation,


\boxed{y=-3x+11}

Hope this helps. :)

User Malaury Boudon
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