Question

lyassini: Do the points (4,3), (2,0) and (-18,-12) lie on the same line? do I have to fined the slopes?

Answer 1

You can solve for the equation of a line in 2D, say the first 2 points, and you'll get y=3/2x -3, now plug in the third point to see if the equation is satisfied or not, in this case, it isnt because you'd get something like 12=30, so to conclude, they are not on the same line.

Answer 2

Thanks :) what I actually did is i found the slop of point 1 and 2, then the slope of point 2 and 3...the slopes were not equal... and i conclude that the points were not on the same line :)))

Answer 3

That works too!

Answer 4

Great!