COMEDK · Maths · 21. Matrices
Solution of \(x-y+z=4 ; x-2 y+2 z=9\) and \(2 x+y+3 z=1\) is
- A \(x=-4 ; \quad y=-3 ; \quad z=2\)
- B \(x=-1 ; \quad y=-3 ; \quad z=2\)
- C \(x=2 ; \quad y=4 ; \quad z=6\)
- D \(x=3 ; \quad y=6 ; \quad z=9\)
Answer & Solution
Correct Answer
(B) \(x=-1 ; \quad y=-3 ; \quad z=2\)
Step-by-step Solution
Detailed explanation
The given system of linear equations is: (1) \(x - y + z = 4\) (2) \(x - 2y + 2z = 9\) (3) \(2x + y + 3z = 1\) Subtract equation (1) from equation (2): \((x - 2y + 2z) - (x - y + z) = 9 - 4\) \(-y + z = 5\) --- (4) Multiply equation (1) by 2 and subtract from equation (3):…
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