MATH PLEASE HELP 15PTS!!!

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.

Respuesta :

80+30x=y  80+30x5=230
10x^2-20=y  10x5^2-20=230
x=5 hours