Yes, businesses dealt in US dollars.
Prices for major things like cars and apartments were in so called "conventional units" (у.е., условная единица), widely known euphemism for US dollars. [1] Cash dollars were very common for these purchases.
For groceries, rubles were used.
For things like washing machines stores had prices in "conventional units", with a daily changing definition of them.
If you could save, you would do it in USD cash. Exchanging between rubles and dollars was very common and cheap. Everybody knew where cash currency traders ("валютчики") were, usually on the main city square. (I think trading currencies outside of banks was illegal, but police looked away, due to corruption and light/no punishment at the time.)
Salaries for domestic jobs were mostly in rubles, with disastrous consequences. Middle class had almost ceased to exist.