How did business respond when the 1886 strike for the eight-hour day successfully "paralyzed most of the industries in chicago"?

The companies responded by either giving them a choice to work 8 hours and get reduced pay, or just gave them the same paycheck for 8 hours of work. They were unhappy because of this however so there were many strikebreakers who with the police managed to cause complete chaos which even resulted in deaths of people.

The 1886 strikes culminated in the Haymarket affair, in which the demonstrations exploded into violence. Backed by business owners, the authorities took this incident as an opportunity to crack down on the demonstrations, outlawing picketing and arresting hundreds of protesters. As such, the businesses in the area were largely able to avoid the need to give in to labor demands at this time, and it was not until later that pro-labor sentiment prevailed.