Solve the following questions.
, find AB. Hence, solve the system of equations:
x – 2y = 10, 2x + y + 3z = 8 and – 2y + z = 7
A = 
B = 
AB = 
AB = 
Now, we can see that it is AB = 11I. where I is the unit Matrix
Or, A – 1 = 
Now the given equation can be written as:
A X B
Or, X = A – 1B
= 
= 
X = 
Hence, x = 4,y = – 3 and z = 1
8