Problem Solving

Hi,

I'm trying to reacquaint myself with coordinate geometry. On page 137 of the 12th edition, there's a graph with two points: (-2,4) and (3,-3). How do you determine which pair is (x1, y1) and which pair is (x2, y2), for the slope formula?

Thanks,
David

From your example:

(-2,4) & (3,-3)
(x1,x2) & (y1,y2)

So the slope is: (-3-4)/(3-(-2))= -7/5 = -1.4

The order of the given points does not matter though.

(3,-3) & (-2,4)

Slope: (4-(-3))/(-2-3) = 7/(-5) = -1.4

The only thing you have to remember is that points in the coordinate plane are always given as (x-coordinate,y-coordinate). With that in mind, you can't go wrong.