May you guys explain every step of 4/5x=64

Which graph represents the solution of the inequality?

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.

Solve the following pair of equations for x and y: ax/b_ by /a= a +b; ax - by = 2ab