Answer:
1. No Solution, 2. Unique Solution, 3. Infinitely Many Solutions
Explanation:
1. If two lines are parallel, they share no common points, and no answers.
2. y = 3x + 4 and y = 1/2x + 5 are not parallel and not equivalent, therefore, they have one solution.
3. Simplified, the two equations are z + 2y = 10 and z + 2y = 10, therefore they are equivalent and they have solutions for as far as the line extends, which is infinitely.