I need help with this question. Please also explain how you got your answer.

The solution set for 5v2 – 125 = 0 is

The total cost of anja’s trip to the dentist was $628.35. she paid a flat fee of $89.95 which included the checkup and cleaning and then had 4 cavities filled, each of which cost the same amount. which shows the correct equation and value of x, the cost of each cavity filling?

Abcd is a square. what is the measure of angle bac