The answer is $1644.
she make 12 visits with a co-payment of $15. 15x12 = 180
305 x 12 = 3660 (total cost of all appointments)
3660 x .40 = $1464 (total cost times her 40%)
$1464 + $180 = $1644 (you must add co-payment to total cost)
hello something is wrong with the question. if ab= AC, and AC = BC, AB=BC, it'd make this an equilateral triangle and the degree wouldn't be 20 degrees