Is This A Legal Eviction?

My landlord is saying hes going to evict me. First legally this triplex should not be rented i learned that after i got in here and im only staying cause with the economy problems its the only place i can afford he never had me sign a lease and the plumbing and electricity is all messed up and theres mold growing through the walls and its definately not up to date. i payed 200 on my rent yesterday and owe 400 more. I live in utah well anyways he text me saying consider this your 3 day pay or vacate notice for past due rent. My question is is this a legal eviction? I have really bad health problems currently and with the way my health is id preobably get even sicker living in the snow and chances are id die because its my kidney that im having problems with.