Jawabanmu

2014-09-12T10:53:54+07:00
  \left[\begin{array}{ccc}1&1\\2&-1\\\end{array}\right]    \left[\begin{array}{ccc}x\\y\end{array}\right]   \left[\begin{array}{ccc}3\\0\end{array}\right]
  \left[\begin{array}{ccc}x\\y\end{array}\right]  \frac{1}{-3}    \left[\begin{array}{ccc}-1&-2\\-2&1\end{array}\right]    \left[\begin{array}{ccc}3\\0\end{array}\right]
  \left[\begin{array}{ccc}x\\y\end{array}\right]   \left[\begin{array}{ccc} \frac{1}{3} & \frac{2}{3}\\ \frac{2}{3}& \frac{-1}{3}  \end{array}\right]    \left[\begin{array}{ccc}3\\0\end{array}\right]
  \left[\begin{array}{ccc}x\\y\end{array}\right]   \left[\begin{array}{ccc}1\\2\end{array}\right]
1/-3 nya dari mana ?
1/det-nya jadi 1/1.(-1)-1.2
2014-09-12T10:56:14+07:00
X+y = 3
2x - y = 0
--------------  +
3x = 3
x = 1

x+y = 3
1 + y = 3
y = 3 - 1
y = 2