chendawg wrote:If sq rt (3-2x) = sq rt (2x) + 1, then 4x^2=
A. 1
B. 4
C. 2 - 2x
D. 4x - 2
E. 6x - 1
Source: OG 12
OA after some discussion.
Since none of the answer choices contains a √, we need to perform algebra that will clear all the √ symbols:
√(3-2x) = √2x + 1
[√(3-2x)]² = (√2x + 1)²
3 - 2x = (√2x + 1)(√2x + 1)
3 - 2x = 2x + √2x + √2x + 1
2 - 2x = 2x + 2√2x
1 - x = x + √2x
1 - 2x = √2x
(1 - 2x)² = (√2x)²
(1 - 2x)(1 - 2x) = 2x
1 - 2x - 2x + 4x² = 2x
4x² = 6x - 1.
The correct answer is
E.
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