He solution to the system of equation below is (? 2, ? 1). 2x ? 3y = ? 1 11x ? 9y = ? 13 when the first equation is multiplied by ? 3, the sum of the two equations is equivalent to 5x = ? 10. which system of equations will also have a solution of (? 2, ? 1)? (a)5x = ? 10 11x ? 9y = ? 13 (b)2x + 9y = ? 1 11x ? 9y = ? 13 (c)? 6x + 9y = ? 1 11x ? 9y = ? 13 (d)? 6x + 3y = ? 1 5x = ? 10