If (r, s) is on the line y = 3x + 2, then s = 3r + 2. That's what we want to know.
From 1), either:
3r + 2 - s = 0, that is, s = 3r + 2
OR
4r + 9 - s = 0, that is, s = 4r + 9
Since we have no way to know which case is true, 1) is insufficient.
From 2), we similarly get two cases.
Taken together, 3r + 2 - s must be zero, since s cannot be equal to both 4r + 9 and to 4r - 6. So C.
Good luck on your test, Hemant! I hope it goes well.
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