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y = (x+a)(x+b)
y = x^2 + x(a+b) + ab ---> ST1
If we look at statement 1, a+b = -1
So the eqn becomes y = x^2 - x + ab
This is insufficient as a and b are unknown...
Look at statement 2, the curve intersects y -axis at (0,-6)
Substituting these values in ST1, we imply ab=-6. But still this is insufficient as a+b is unknown.
Combining statement 1 and 2, we get y = x^2 -x -6
In x axis , y = 0. So x^2 -x -6 = 0
x = 3,-2.. The points are (3,0) and (-2,0)
Hence C.
