Algebramedium · Past Paper
For what value of k will the system 2x + 3y = 7 and 4x + ky = 14 have infinite solutions?
A3
B6
C9
D12
✓ Correct Answer: B — 6
For infinite solutions, ratios of coefficients must be equal: 2/4 = 3/k. So k = 6.
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