iMac as monitor for new Macbook Air
Would it be possible (and efficient) to just use my iMac (mid-2007, OS X 10.11.16) as a larger monitor for my new Macbook Air? What cables would be optimal, if so? I don't want to use the iMac for anything other than as a monitor. Would the iMac display even stack up against a current 4K ~$400 Dell or LG monitor?
iMac, OS X 10.11