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## (-2,r), (6,7), m=1/2. How do you find r?

How do you find the value of r so the line that passes through each pair of points has the given slope.

You have two points, which can be labeled (x1, y1) and (x2, y2).

The formula for the slope between two points is m = (y2 - y1 )/(x2 - x1).

We can fill in the pieces:

1/2  =  (7 - r)/(6 - (-2))

0r       (7 - r)/(6 + 2) = 1/2

(7 - r)/8    = 1/2

Now multiply both sides by 8 to clear 8 from the denominator on the left:

(7 - r)  = 8(1/2)
7 - r =  4
r = 3

slope is rise over run

so

r-7      =     1

-2-6            2

we start by simplifying as much as we can

r-7   =  1

-8         2

next we get rid of the denominators by cross multiplying. we multiply the bottoms by the tops on the other side of the equation

2(r-7)=-8*1

then simplify

2(r-7)=-8

then we distribute the 2   a(b+c)=ab+ac

2r-2*7=-8

2r-14=-8

then cancel the 14 by adding 14 to both sides

2r-14+14=-8+14

2r=6

then cancel the 2 by dividing both sides by 2

2r/2=6/6

r=3

so r has to be 3

did you understand if you have any questions please comment.