Determine whether the given ordered pair is a solution if the given system. Do not solve with graphing or substitution or elimination

a$.(-2,1)\{\begin{array}{c}3x+5y=-1\\ 2x+7y=3\end{array}$

b$.(3,-5)\{\begin{array}{c}4x+2y=2\\ 6x-y=12\end{array}$