Question

List two coordinates of two locations that, when connected, create a positive slope. Prove they are positive by putting them into the slope formula.
List two coordinates that, when connected, create a negative slope. Put into slope formula.

my positive points are (2,5) (12,19)
my negative points are (12,19) (21,5)
(Theyre the two sides of a triangle.
Im a little confused on how to put them into slope form.