What is the domain of the graph

If the graphs of the linear equations in a system are parallel, what does that mean about the possible solution(s) of the system? a. there are infinitely many solutions. b. there is no solution. c. there is exactly one solution. d. the lines in a system cannot be parallel.

He concluded that a heavier object dropped from the same height as a lighter object will land

Simply 8x squared + 5(7x squared- x) - 2x =