Let λ be a real number for which the system of linear equations
x+y+z=6,
4x+λy−λz=λ−2 and
3x+2y−4z=−5
has infinitely many solutions. Then λ is a root of the quadratic equation:
Held on 10 Apr 2019 · Verified 6 Jul 2026.
λ2+3λ−4=0
λ2−λ−6=0
λ2−3λ−4=0
λ2+λ−6=0
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