Use substitution to solve the system.
\[
\begin{aligned}
3 x+7 y & =-42 \\
4 x-y & =6
\end{aligned}
\]

Select the correct choice below and, if necessary, fill in the answer box to complete your choice.
A. The solution is $\square$. (Type an,ordered pair.)
B. There àre infinitely many solutions.
C. There is no solution.

Answer

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Answer

So, the solution to the system of equations is $\boxed{(0, -6)}$.

Steps

Step 1 ：The system of equations is given as follows: \[\begin{aligned} 3 x+7 y & =-42 \\ 4 x-y & =6 \end{aligned}\]

Step 2 ：First, solve the second equation for y to get $y = 4x - 6$.

Step 3 ：Substitute $y = 4x - 6$ into the first equation to get $3x + 7(4x - 6) = -42$, which simplifies to $31x - 42 = -42$.

Step 4 ：Solve the equation $31x - 42 = -42$ to get $x = 0$.

Step 5 ：Substitute $x = 0$ back into the equation $y = 4x - 6$ to get $y = -6$.

Step 6 ：So, the solution to the system of equations is $\boxed{(0, -6)}$.