(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

[tex]x = \sqrt{4 - 3x}[/tex]

3. The attempt at a solution

[tex]x^2 = 4 - 3x[/tex]

[tex]x^2 + 3x - 4 = 0[/tex]

[tex](x+4)(x-1) = 0[/tex]

[tex]x + 4 = 0[/tex]

[tex]x = -4[/tex]

[tex]x -1 = 0[/tex]

[tex]x = 1[/tex]

Plugging back into the original equation, -4 doesn't work and 1 does work. But, if I plug it into the quadratic they both work. So which is it?

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# Solving an equation

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