Answer:
1. x = -7
2. x = 6/13
3. x = 7/12
Step-by-step explanation:
1. x = 21 / -3
x = -7
2. 13x = 6
x = 6 / 13
x = 6/13
3. -12x = -7
x = -7 / -12
x = 7/12
<em>Hope that helps!</em>
Answer: D. 16.33