1. A
Since parallel lines never cross, then there can be no intersection; that is, for a system of equations that graphs as parallel lines, there can be no solution. This is called an "inconsistent" system of equations, and it has no solution.
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2. C
That's right. If a system of equations has a solution, then their graphs intersect, and the point where they intersect is the solution because it's the point that satisfies each equation in the system.
Straight-line graphs with the same slope are parallel lines, and they never intersect, which is another way of saying they have no solution.