10. (5,8)(-3,7)
slope = (7 - 8) / (-3 - 5) = -1 / -8 = 1/8
11. (5,-2)(3,-2)...since both y values are the same, this line is a horizontal line with a 0 slope.
12. (-4,7)(8,-1)
slope = (-1 - 7) / (8 - (-4) = -8 / (8 + 4) = -8/12 = - 2/3
13. (6,-3)(6,4)....since both x values are the same, this line is a vertical line with a slope that is undefined
14. -2/5