SOLUTION: I need assistance with writing point-slope form for an equation with the slope and one point already given. one example is "what is the point-slope form of a line through (4,-4) wi

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Question 636044: I need assistance with writing point-slope form for an equation with the slope and one point already given. one example is "what is the point-slope form of a line through (4,-4) with a slope of -9/4?" I don't even know how to begin solving this problem. I practically need a lesson on how to do this kind of thing in general.
Answer by ewatrrr(10682) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

Using the standard slope-intercept form for an equation of a line y = mx + b

  where m is the slope and b the y-intercept.

line through (4,-4) with a slope m =  -9/4

y+=+highlight%28-9%2F4%29x+%2B+b

-4+=+highlight%28-9%2F4%29%2A4+%2B+b  |Using ordered pair (x,y): (4,-4)  to solve for b

5 = b

 y = (-9/4)x + 5   (Note: line slants to the left (back 4 Up 9) from point(4,-4)

using point-slope form as the directions state

y+-+y%5B1%5D+=++%28-9%2F4%29%28x+-+x%5B1%5D%29

y+-+%28-4%29+=++%28-9%2F4%29%28x+-+4%29

y+%2B+4+=++%28-9%2F4%29%28x+-+4%29      || which also says:  y = (-9/4)x + 5)