#### Answer

$\{(2,-2)\}$

#### Work Step by Step

1. y has opposite signs in the equations.
Multiply the first equation with 6, the second with 7,
which will lead to eliminating y:
$\left\{\begin{array}{llll}
36x & +42y & +12 & =0\\
49x & -42y & -182 & =0
\end{array}\right.$
2. ... add the equations and solve
$85x-170=0\qquad/+170$
$85x=170\qquad/\div 85$
$x=2$
3. Back-substitute into one of the initial equations
$6x+7y+2=0$
$6(2)+7y+2=0$
$7y+14=0\qquad/-14$
$7y=-14\qquad/\div 7$
$y=-2$
4. Write the solution as an ordered pair.
Solution set: $\{(2,-2)\}$