Help please linear equations

A company rents out folding chairs for events with delivery included. The company offers 50 chairs for $100 and 150 chairs for $250.
a) Determine the cost of delivery that the company has included in their rates.
Cost of delivery:

b) An event organiser is expecting 600 people and has budgeted $900 for chair rental. Write and solve a two-variable equation to determine whether they will be able to rent enough chairs to seat all their guests for their budgeted amount.
Equation:

Will the organiser be able to meet their budget? Show how you know: