imac 2011 as display monitor with Macbook Pro 2017
I am trying to connect my 21.5 inch mid 2011 imac to my macbook pro 2017 so I can use the imac as a monitor. I have tried the Techdoty usbC to mini display port cable but it didn't work. I went to the apple store and the guy sold me a thunderbolt 3 to thunderbolt 2 adapter. He said I could use my firewire cable to attach. Well that doesn't work because a firewire cable does not fit in a thunderbolt 2 adapter. Help!
iMac 21.5", macOS 10.13