SOLUTION: what is the equation for a line that passes through the following points, (9,3) and (19,-17)?

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Question 1063600: what is the equation for a line that passes through the following points, (9,3) and (19,-17)?
Found 2 solutions by reviewermath, josgarithmetic:
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
Q: what is the equation for a line that passes through the following points, (9,3) and (19,-17)?
Tutorial:
First, compute the slope.
The slope is equal to "change in y" divided by "change in x"
slope, m = %28-17+-+3%29%2F%2819+-+9%29+=+-2
Next, we use the point-slope form y+-+y%5B1%5D+=+m%28x+-+x%5B1%5D%29
We choose (x%5B1%5D, y%5B1%5D) = (9, 3)
y - 3 = -2(x - 9)
y - 3 = -2x + 18
highlight%28y+=+-2x+%2B+21%29 is the equation of the line

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Slope-intercept equation form, y=mx+b
slope is m
vertical axis intercept is b


y=%28%283-%28-17%29%29%2F%289-19%29%29x%2Bb

y=%28%2820%29%2F%28-10%29%29x%2Bb

y=-2x%2Bb


y=mx%2Bb
y-mx=b
b=y-mx
Pick either given point, choosing (9,3) here.
b=3-%28-2%29%2A9
b=3%2B18
b=21

Completed equation, highlight%28y=-2x%2B21%29