Answer:
a) Total cost =

b) 11 days
Explanation:
Given:
(a)
Number of days in hospital =

Cost of operation = $ 500
Cost of nursing per day = $170
∴ Cost of nursing for
days = $

Therefore, the expression for total cost of her operation and nursing care is given as,
, where
is the total cost.
(b)
Given:
Total cost of operation =

Using the expression obtained in (a), we solve for
.

Plug in 2370 for C and solve for
. This gives,

Therefore, Angharad stayed in hospital for 11 days.