9514 1404 393
Answer:
(a) 4x+89.95=628.35; x = $134.60
Explanation:
The total cost (628.35) is the cost per cavity (x) times the number of cavities (4), added to the flat fee (89.95). The equation for that is ...
4x +89.95 = 628.35
The solution to that is ...
x = (628.35 -89.95)/4 . . . . . subtract the constant, divide by 4
x = 134.60