Solve the system by the substitution method.
\[
\begin{aligned}
x y & =30 \\
3 x-y & =-9
\end{aligned}
\]
Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution set is
(Type an ordered pair. Use a comma to separate answers if needed.)
B. There is no solution.
Answer
The solution set is \(\boxed{(-5, -6), (2, 15)}\).
Step 1 ：Express y in terms of x from the first equation: \(y = \frac{30}{x}\).
Step 2 ：Substitute \(y = \frac{30}{x}\) in the second equation and solve for x.
Step 3 ：The solutions for x are -5 and 2.
Step 4 ：Substitute x = -5 and x = 2 back into the equation \(y = \frac{30}{x}\) to find the corresponding values of y.
Step 5 ：The solutions for y are -6 and 15 when x = -5 and x = 2 respectively.
Step 6 ：The solution set is \(\boxed{(-5, -6), (2, 15)}\).
