Q41 of 98 Page 310

= 4; = 0;

= 2. (x, y, z ≠ 0)



To find: - x , y , z


Given set of lines are : -


= 4


= 0


= 2


Converting following equations in matrix form,


AX = B



R2 – 2R1


R3 – R1



Again converting into equations we get








Z = 1



- 1 - 1


X =


∴ x = , y = , z =


More from this chapter

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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.


 40

= 10, = 10,

= 13


Ans. x = , y = , z =


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.

 43

The cost of 4 kg potato, 3 kg wheat and 2 kg of rice is ₹ 60. The cost of 1 kg potato, 2 kg wheat and 3 kg of rice is ₹45. The cost of 6 kg potato, 2 kg wheat and 3 kg of rice is ₹70. Find the cost of each item per kg by matrix method.