#### Answer

Please see "work step by step" for explanation.

#### Work Step by Step

Producing a commodity involves a cost of production , which is a function C(x), where x is the number of units produced.
The reason for producing the commodity is to sell it at a unit price, generating revenue, which is a function R(x), of units sold.
The break-even quantity is the number of units x for which the cost equals the revenue, which we find by solving
C(x)=R(x)
Breaking even means reaching the point where we are no longer at a loss, but have not yet generated any profit.