very strange problem with old house

hi first time posting need some ideas with a very odd problem. Last night I noticed that half the outlets in my living room had stopped working so first thing I did was check the breaker none triped. So I do up stairs and my girlfriend turns the dryer on and the tv comes on. Shut the dryer off tv goes off. The dryer is on its own deditcated 50amp 220 circuit. The living room outlets are on 15 amp of there own. Any ideas im stumped

very strange problem with old house