Solve each of the following systems of equations. Find all solutions. (a)\( \begin{align*} x+y&=-1,\\ 3x &= 4-3y. \end{align*} \) (b)\( \begin{align*} 3x - 4y + 2&=0,\\ 10 - 10y& = 10y - 15x. \end{align*}\)
1. (x,y) = (-4,3).
2. (x,y) = (8, 13/2).
+12 
