Math !

skylar repairs microwaves. her revenue, in dollars, can be modeled by the equation y = 80 + 30x, where x is the number of hours spent repairing microwaves. her overhead cost, in dollars, can be modeled by the equation y = 10x^2 − 20 , where x is the number of hours spent repairing microwaves.
after how many hours does she break even?

note: the phrase break even refers to the value where the two functions are equivalent.