Find the solution to the system by the substitution method. Check your answers. $$ \begin{array}{r}7 x+4 y=86 \ x+2 y=-2\end{array} $$ Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

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Solve the system of equations $$ 7x+4y=86;x+2y=-2 $$.
Solve the system of equations by following steps:
- step0: Solve using the substitution method:
  $$\left\{ \begin{array}{l}7x+4y=86\x+2y=-2\end{array}ight.$$
- step1: Solve the equation:
  $$\left\{ \begin{array}{l}7x+4y=86\x=-2-2y\end{array}ight.$$
- step2: Substitute the value of $$x:$$
  $$7\left(-2-2yight)+4y=86$$
- step3: Simplify:
  $$-14-10y=86$$
- step4: Move the constant to the right side:
  $$-10y=86+14$$
- step5: Add the numbers:
  $$-10y=100$$
- step6: Change the signs:
  $$10y=-100$$
- step7: Divide both sides:
  $$\frac{10y}{10}=\frac{-100}{10}$$
- step8: Divide the numbers:
  $$y=-10$$
- step9: Substitute the value of $$y:$$
  $$x=-2-2\left(-10ight)$$
- step10: Simplify:
  $$x=18$$
- step11: Calculate:
  $$\left\{ \begin{array}{l}x=18\y=-10\end{array}ight.$$
- step12: Check the solution:
  $$\left\{ \begin{array}{l}x=18\y=-10\end{array}ight.$$
- step13: Rewrite:
  $$\left(x,yight) = \left(18,-10ight)$$
The solution to the system of equations by the substitution method is $$ (x,y) = (18,-10) $$.
The solution is $$ x = 18 $$ and $$ y = -10 $$.

Find the solution to the system by the substitution method. Check your answers. \( \begin{array}{r}7 x+4 y=86 \\ x+2 y=-2\end{array} \) Select the correct choice below and, if necessary, fill in the answer box to complete your choice.

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