the value of 3 x² + 2 x - 1

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the value of 3 x² + 2 x - 1

by sanju09 » Fri Jul 30, 2010 6:14 am
What is the value of 3 x² + 2 x - 1?

1. x² + 2 x = 0.
2. x = -2.

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by selango » Fri Jul 30, 2010 6:23 am
3X^2+2x-1?

stmt1,

x^2+2x=0

x(x+2)=0

x=0 or x=-2

Insuff

stmt2,

x=-2

Suff

Pick B
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by uhsa » Fri Jul 30, 2010 11:26 am
Anand gave a great reply. I need to pick up on that. I did it this way:

3x^2 + 2x -1 == 3(x^2 + 2x) -4x -1 ==> -4x -1 is left ==> Insuff.

x = -2 ==> You get the value == Sufficient.