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What is the equation in point-slope form of a line that passes through the points (7, −8) and (−4, 6) ?

User Solidgumby
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1 Answer

1 vote

Hello from MrBillDoesMath!


Answer: y - (-8) = (-14/11) (x -7) or y + 8 = (-14/11) (x-7)


Steps:

Let's call point (7, -8) (x1,y1) and point (-4,6) (x2,y2). The point slope equation of a line through (x1, y1) is

y- y1 = m(x-x1)


where "m" is the slope of the non-vertical line. Recall that m is rise/run or

m = (y2- y1)/(x2-x1).

In our case

m = (6 - (-8))/( -4 - 7) = (6 + 8)/ (-11) = - 14/11

The point-slope equation becomes

y - (-8) = (-14/11) (x -7)

This can be rewritten as y + 8 = (-14/11) (x-7)

As a final check, you should verify that this equation passes through the original points using substitution!

Regards, MrB.



User Sharky Bamboozle
by
7.2k points
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