Which of these strategies would eliminate a variable in the system of equations? \begin{cases} 6x + 5y = 1 \\\\ 6x - 5y = 7 \end{cases} ⎩ ⎪ ⎪ ⎨ ⎪ ⎪ ⎧ ​ 6x+5y=1 6x−5y=7 ​