Carcass wrote:

If \((2x + 1)(x – 5) = 2 (x^2 – 1)\), what is the value of x?

A. \(- \frac{1}{3}\)

B. \(- \frac{1}{5}\)

C. \(0\)

D. \(\frac{1}{3}\)

E. \(\frac{1}{2}\)

pranab01's solution above is exactly how I'd solve the question.

However, if your algebra skills aren't that great, you can still solve the question by

testing the answer choicesGIVEN EQUATION: (2x + 1)(x – 5) = 2 (x² – 1)

A) -1/3

Replace x with

-1/3 to get: (2

(-1/3) + 1)(

-1/3 – 5) = 2(

(-1/3)² – 1)

Simplify: (-2/3 + 1)(-16/3) = 2(1/9 - 1)

Simplify more: (1/3)(-16/3) = 2(-8/9)

Evaluate: -16/9 = -16/9 PERFECT!!

Answer: A

Cheers,

Brent

_________________

Brent Hanneson – Creator of greenlighttestprep.com

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