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JEE MAIN 2025
22-01-2025 SHIFT-2
Question
If the system of linear equations : $$ \begin{aligned} & x+y+2 z=6 \\ & 2 x+3 y+a z=a+1 \\ & -x-3 y+b z=2 b \end{aligned} $$ where $a, b \in \mathbf{R}$, has infinitely many solutions, then $7 a+3 b$ is equal to:
Select the correct option:
A
9
B
16
C
22
D
12
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
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JEE Main
Mathematics
Medium
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