Is these algebraic expression correct

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The forum discussion centers on verifying the correctness of various algebraic expressions. The first expression, (x - 3)² = 4, is incorrect as substituting x = -1 or x = -5 does not yield a product of zero. The second expression, 2x + 4 / x + 1 = x - 8 / 2x - 1, is valid, and the next step involves simplifying to a quadratic equation. The third expression, involving multiple manipulations, requires clearer formatting for accurate assessment, as the current presentation leads to confusion.

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1.(x - 3)2 = 4
x2 - 6x + 5 = 0
(x - 1)(x - 5) = 0
x = -1, -5
(is this correct)

2. 2x + 4 / x +1 = x - 8 / 2x - 1
(2x + 4)(2x - 1) = (x - 8)(x + 1
4x2 - 2x + 8x - 4 = x2 - 7x -8
4x2 - 6x - 4 = x2 - 7x - 8
(where do i go from here)

3. (x / 3) - (y / 2) = -1
(y / 2) = -4 - 3x
6x + y = -8
y = -8 - 6x
(x / 3) - (-4 - 3x) = -1
(10 / 3) x + 4 = -1
x = -5 / (10 / 3) = (-3 / 2) x = -3 / 2
6(-3 / 2) + y = -8
y = -8 + 6(-3 / 2)
y = -8 + (-18 / 2)
y = (-144 +- 16 / 16) y = -10
(is this correct)
 
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1. No, they should be positive. If you plugged in either x=-1 or x=-5, you'd see that product didn't equal 0.

2. For this question, is what you're asking [tex]\frac{{2x + 4}}{{x + 1}} = \frac{{x - 8}}{{2x - 1}}[/tex]? If so, it looks good. Now you simply want to subtract [tex]x^2 - 7x - 8[/tex] from both sides so you have 0 on the right side and a simple quadratic on the left.

3. This looks a little confusing. Can you put spaces between each set of equations so we know exactly what you're doing? If the third line is suppose to be manipulation of the first line, it doesn't look correct.
 

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