JAMIA 2023 — Mathematics PYQ
JAMIA | Mathematics | 2023The system of linear equations
a+2b+3c=7
2a+4b+c=12
3a+ 6b+4c=20
Choose the correct answer:
- A.
has a unique solution
- B.
has no solution
(Correct Answer) - C.
has infinite number of solutions
- D.
has two solutions
has no solution
Explanation
1. Given System of Equations
a+2b+3c=7…(1)
2a+4b+c=12…(2)
3a+6b+4c=20…(3)
2. Matrix Representation
We can write the system as AX=B:
123amp;2amp;4amp;6amp;3amp;1amp;4abc=71220
3. Row Operations (Gaussian Elimination)
We will perform operations on the Augmented Matrix [A∣B]:
[A∣B]=123amp;2amp;4amp;6amp;3amp;1amp;4amp;∣amp;∣amp;∣amp;7amp;12amp;20
Perform R2→R2−2R1 and R3→R3−3R1:
100amp;2amp;0amp;0amp;3amp;−5amp;−5amp;∣amp;∣amp;∣amp;7amp;−2amp;−1
Perform R3→R3−R2:
100amp;2amp;0amp;0amp;3amp;−5amp;0amp;∣amp;∣amp;∣amp;7amp;−2amp;1
4. Analyzing the Result
Look at the third row:
0a+0b+0c=1
0=1
This is a contradiction. Mathematically, this means that the planes represented by these equations do not have a common point of intersection.
5. Final Conclusion
Since we arrived at an impossible statement (0=1), the system of equations is Inconsistent.
Result:
The system has No Solution.

