Q8 of 75 Page 8

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


More from this chapter

All 75 →
8

Solve the following questions.

If , find A – 1. Using A – 1, solve the system of linear equations:


x – 2y = 10, 2x + y + 3z = 8, – 2y + z = 7.

 8

Solve the following questions.

, find A – 1 and hence solve the following system of equations:


3x – 4y + 2z = – 1, 2x + 3y + 5z = 7, x + z = 2.

 8

Solve the following questions.

If , find A – 1. Using A – 1, solve the system of linear equations


x – 2y = 10, 2x – y – z = 8, – 2y + z = 7.

 8

Solve the following questions.

Given , find BA and use this to solve the system of equations y + 2z = 7, x – y = 3, 2x + 3y + 4z = 17