Entrepreneurs on the British programme Dragons' Den usually offer investors equity in exchange for money.
Equity means an ownership stake in a company. During a pitch, an entrepreneur normally states the amount of investment requested and the percentage of the business offered. The dragons then assess the company’s value, financial prospects, management team, and the proposed terms.
If a dragon makes an offer, the negotiation may change both the amount invested and the percentage of ownership. More than one dragon may also collaborate on an offer. A deal shown on television is subject to further checks and legal documentation, so an on-screen agreement is not necessarily the final completed transaction.
A salary is payment for work, not ownership. A patent protects an invention, and a franchise is a business arrangement allowing another operator to use a brand and system. Those can be relevant to a company, but they are not the usual thing offered to the dragons for investment.