matriks (di atas x+y di bawah 2x-15)=(d atas 4x-5y d bawah 6x-7y) nilai x dan y brapa?

[tex] \left[\begin{array}{ccc}x+y\\2x -15\end{array}\right] = \left[\begin{array}{ccc}4x - 5y\\6x-7y\end{array}\right] \\ x + y = 4x - 5y \\ 3x - 6y = 0 \\ x - 2y = 0 \\ x = 2y....(i)\\ \\ \\ 2x - 15 = 6x - 7y \\ 4x - 7y = -15...(ii)\\ \\ subs (i) ke (ii) [/tex]

didapat x = -15 dan y = -30