My LCD screen is broken on my IMac and I want to attach an hdmi cable to connect to my tv, is there a keyboard shortcut to connect?

Hi! Please help! My LCD screen is broken and I want to connect my iMac through an hdmi cord to my TV. I had it connected before my screen completely died but it turned off and reverted back to the default settings. Are there any keyboard shortcuts for this as my computers on but I have no screen to see what I am doing? Help would be appreciated please!!