John thunderhawk is making furniture he finds that to design a particular cabitnet and set up his shop to produce it cost $1800. then the labor and supplies to build each one are $400. so his cost,y, for x items is respentented by y=1800+400x. he can sell the cabinets for $600. so his revenue y is repesentive by y=600x. the solution tothis system of equations is his break even piont the point beyond which he starts making profit. How many cabinets must he sell to break even?