Find the slope of the following: (-1,8) and (12, -5)

Answer 1

8 minus -5 = 8 - -5 = 8+5 = 13 = change in y values

-1 minus 12 = -1 - 12 = -13 = change in x values

slope = change in y values divided by change in x values ("rise over run") = 13/-13 = - 1

slope = negative one

best way though to see this is just plot a rough sketch. It's downward sloping, so it has to be negative slope. and it's like a 45 degree line downward sloping, which is -1