SOLUTION: If the points (-1, 7) and (k,-2) are on a line with slope -1, what is the value of k? F)-8 G)8 H) 11 J) -6

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Question 239583: If the points (-1, 7) and (k,-2) are on a line with slope -1, what is the value of k?
F)-8 G)8 H) 11 J) -6
Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
The Point-Slope Form formula is: y-y1=m%28x-x1%29
.
All you need to do here is substitute the values and solve for missing value.
.
m=-1 (m=slope)
y=-2
y1=7
x=k
x1=-1 (the missing value)
.
y-y1=m%28x-x1%29
-2-7=-1%28k-%28-1%29%29
-9=-1%28k%2B1%29
-9=-k-1
-8=-k
Now divide by -1 on both sides to determine the value of k.
8=k
.
Done!