pls help I don't know the answer and can you pls explain how you got the answer if you are the first person to do it AND explain hen you will get a brainlist

Asmall business produces and sells balls. the fixed costs are $20 and each ball costs $4.32 to produce. each ball sells for $8.32. write the equations for the total cost, c, and the revenue, r, then use the graphing method to determine how many balls must be sold to break even.