algebra
posted by cathy on .
you have just graduated from college and recently opened a specialty pizza restaurant. Based on surveys conducted in your area, you determine what it is feasible to sell your specialty for $15. The cost for making the pizzas includes a fixed cost of $55 and a labor cost of $4 per pizza. Establish an equation to determine revenue.
Establish and equation to determine cost.
how many pizzas must be sold to break even?

Revenue=15n
cost=55+4n
breakeven, set them equal, solve for n. 
I needto see the whole equation and how it is gotten I have to show my work