Tolong di bantu ya pake cara

Penyelesaian:

= [tex] \left[\begin{array}{cc}x&-2\\-4&y\end{array}\right] + 2 \left[\begin{array}{cc}-1&3\\4&x\end{array}\right] = \left[\begin{array}{cc}y&4\\4&10\end{array}\right] [/tex]
= [tex] \left[\begin{array}{cc}x&-2\\-4&y\end{array}\right] + \left[\begin{array}{cc}-2&6\\8&2x\end{array}\right] = \left[\begin{array}{cc}y&4\\4&10\end{array}\right] [/tex]

jumlah kan dengan penjumlahan matriks, didapat:
x - 2 = y          -> x - y = 2         (persamaan 1)
y + 2x = 10     -> 2x + y = 10    (persamaan 2)

eliminasi persamaan 1 dengan persamaan 2:
x - y = 2
2x + y = 10
---------------   +
3x = 12
x = 4  (B).