Can someone please do 13 and B for 23 points

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?

How many solutions does the nonlinear system of equations graphed bellow have?

The measures of the legs of a right triangle are 15m and 20m . what is the length of the hypotenuse