In a monopoly market, a firm maximizes its profit by producing output where marginal revenue equals what?

In a monopoly market, a firm maximizes its profit by producing output where marginal revenue equals marginal cost. Marginal revenue is the extra money the firm makes from selling one more unit of its product, while marginal cost is the extra cost of producing that unit. When these two values are equal, the firm is at the best point to maximize profit because producing more would cost more than it earns. For example, if a monopolist sells toys and finds that producing one more toy costs $5 but brings in $5 in revenue, it means they are at the optimal point for profit. If they produced more, they would start losing money, so they stop at that level of output.