tolong bantu dari nomer 3 sampe bawah

itu yg nomor 3 smoga bisa membantu

3.  X +  \left[\begin{array}{ccc}10&0\\2&-1\end{array}\right]  = \left[\begin{array}{ccc}10&-2\\2&-1\end{array}\right] 
     X = \left[\begin{array}{ccc}10&-2\\2&-1\end{array}\right] - \left[\begin{array}{ccc}10&0\\2&-1\end{array}\right]
     X = \left[\begin{array}{ccc}0&-2\\0&0\end{array}\right]

4. \left[\begin{array}{ccc}10&3x\\2y&6\end{array}\right] + \left[\begin{array}{ccc}-6&-5\\-y&2y\end{array}\right] = \left[\begin{array}{ccc}4&7\\y&8\end{array}\right]

x -- > 3x + (-5) = 7
                   3x = 7 + 5
                     x = 12/3
                     x = 4
y -- > 6 + 2y = 8
               2y = 8-6
                 y = 2/2
                 y = 1

Jadi :
x + y = 4 + 1 =5

5. \left[\begin{array}{ccc}x&4\\1&3\end{array}\right] . \left[\begin{array}{ccc}7\\y\end{array}\right] = \left[\begin{array}{ccc}11\\10\end{array}\right]

kalikan akan di temukan :

7x + 4y = 11
7 + 3y = 10

7 + 3y = 10
      3y = 10-7
        y = 3/3
        y = 1

7x + 4y = 11
7x + 4.1 = 11
7x          = 11-4
7x          = 7
x            = 1

maka 
2x - y = 2 - 1 = 1

6.
AB = \left[\begin{array}{ccc}4&5\\5&6\end{array}\right] . \left[\begin{array}{ccc}-6&5\\5&-4\end{array}\right]AB = \left[\begin{array}{ccc}-24+25&20-20\\-30+30&25-24\end{array}\right]AB = \left[\begin{array}{ccc}1&0\\0&1\end{array}\right]

7. 
BA = \left[\begin{array}{ccc}3&-2\\5&-3\end{array}\right] . \left[\begin{array}{ccc}4&5\\5&6\end{array}\right]
BA = \left[\begin{array}{ccc}12-10&15-12\\20-15&25-18\end{array}\right]BA = \left[\begin{array}{ccc}2&3\\5&7\end{array}\right]
BA^-1 = \left[\begin{array}{ccc}2&5\\3&7\end{array}\right]