What are the steps they're using to simplify this?

What is the solution of log2  (3x  -  7)  =  3? 4 5

Suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet.

The cost of using a service is $0.25 per min. what equation correctly represents the total cost c, in dollars, for d days of use?