Solve the Problem $y$ (In Dollars) of Purchasing $x$ Thousand Printed Cards Can Be Approximated By

Solve the problem.
-At a certain copy center, the cost $y$ (in dollars) of purchasing $x$ thousand printed cards can be approximated by $x y+y=60 x$ . Use implicit differentiation to find and interpret $\frac{d y}{d x}$ when $x=1$ and $\mathrm{y}=30$ .

A) $\frac{d y}{d x}=15$ means that additional cards will cost approximately $\$ 15.00$ each.
B) $\frac{d y}{d x}=30$ means that ordering an additional thousand cards will cost approximately $\$ 15.00$ more.
C) $\frac{d y}{d x}=15$ means that ordering an additional thousand cards will cost approximately $\$ 15.00$ more.
D) $\frac{d y}{d x}=30$ means that ordering an additional 30 cards will cost $\$ 1000.00$ more.