How do I write 588.18 in scientific notation

Ihonestly don’t understand this at all

Aschool puts on a play. the play costs $1,200 in expenses. the students charge $4.00 for tickets. there will be one performance of the play in an auditorium that seats 500 people. what is the domain of the function that shows the profit as a function of the number of tickets sold?  

What are the solutions of the system? solve by graphing. y = x^2 + 3x + 2 y = 2x + 2