Answer:
1. 0, 2. -1/2, 3.undefined, 4. -5/3, 5. 6, 6. -2, 7. 23/17
Step-by-step explanation:
y2 - y1 / x2 - x1
1. -18 - -18 / 15 - 6 = 0
2. 16 - 12 / 0 - 8 = -4/8 = -1/2
3. 37 - 2 / -15 - -15 is undefined (can't have 0 as denominator)
4. 30 - 20 / -5 - 1 = 10 / -6 = -5/3
5. -36 - -12 / 4 - 8 = -24 / -4 = 6
6. - 23 - -15 / 11 - 7 = -8 / 4 = -2
7. 100 - 54 / -38 - -72 = 46 / 34 = 23/17