Q40 of 98 Page 310

= 10, = 10,

= 13


Ans. x = , y = , z =



To find: - x , y , z


Given set of lines are : -


= 10


= 10,


= 13


Converting the following equations in matrix form,


AX = B



2R2 – R1


2R3 – 3R1



R3 - 5R2



Again converting into equations we get








Z =



9 – 15 = 4


X =


∴ x = , y = , z =


More from this chapter

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38

If A = , find A - 1.

Using A - 1, solve the following


system of linear equations:


2x + y + z = 1;


X – 2y – z = ;


3y – 5z = 9.


HINT: Here A = ,


X = and B = .


 39

If A = and

B = , find AB.


Hence, solve the system of equations:


x – 2y = 10,


2x + y + 3z = 8 and


- 2y + z = 7.


HINT: AB = (11)I = A = I


A - 1 = B.


 41

= 4; = 0;

= 2. (x, y, z ≠ 0)


 42

The sum of three numbers is 2. If twice the second number is added to the sum of first and third, we get 1. On adding the sum of second and third numbers to five times the first, we get 6. Find the three numbers by using matrices.