Answer:
slope = (y2-y1)/(x2-x1)
15 ) slope = (4 - (-11)) / (17 - (-8 )
= 15/25 = 3/5
17 ) (-7 - (-7))/(5 - -6) = 0
19 ) (5 - -2)/(10 - 10) = 7/0 undefined (vertical line)
21 ) (-16 - -12)/ ( 1 - -7) = -4/8 = -1/2
23) (-4 - -11)/(-2 -1) = 7/-3
