If c is a constant and x is a variable, what is the value of

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by Jay@ManhattanReview » Sun Jan 05, 2020 8:37 pm
BTGmoderatorDC wrote:If c is a constant and x is a variable, what is the value of c in the equation x^2 + 24x + c = 0?


(1) The equation x^2 + 24x + c = 0 has exactly one distinct solution.
(2) C is less than or equal to 144

OA A

Source: Official Guide
(1) The equation x^2 + 24x + c = 0 has exactly one distinct solution.

For a quadratic equation ax^2 + bx + c, if the discriminant b^2 - 4ac = 0, then the quadratic equation ax^2 + bx + c has exactly one distinct solution.

Thus, for the quadratic equation x^2 + 24x + c = 0, we have b^2 - 4ac = 24^2 - 4*1*c = 0 => c = 144. Sufficient

(2) C is less than or equal to 144.

Clearly insufficient.

The correct answer: A

Hope this helps!

-Jay
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