Select all of the expressions that are equivalent to 6+12x

Explain step-by-step how to simplify -5(2x – 3y + 6z – 10).

Which ordered pair (c,d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15

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?