**Official Guide**

If (4 - x)/(2 + x) = x, what is the value of x^2 + 3x -4?

A. -4

B. -1

C. 0

D. 1

E. 2

OA C

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Given: (4 - x)/(2 + x) = x

Eliminate the fraction by multiplying both sides by (2 + x) to get: (4 - x) = (x)(2 + x)

Expand: 4 - x = 2x + x²

Add x to both sides: 4 = x² + 3x

Subtract 4 from both sides: 0 = x² + 3x - 4

PERFECT! The question asks us to find the value of x² + 3x - 4, and we just showed that the expression equals 0

Answer: C