Interpretations
b1=75.50 means that for every additional year of a car’s age, repair cost will rise by $75.50.
b0=49.50 means that if a car is zero years old (x=0), the repair cost would be $49.50.
We shouldn’t put too much emphasis in the interpretation of b0. It acts as a sponge, capturing many other effects on the dependent variable and is thus unreliable for much explanatory power.