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Did I solve the following quadratic equation correctly.

$$W(W+2)-7=2W(W-3)$$

I got.

$$W^2-8W+7$$ Then for my solution I got.

$$(W-1)(W-7)$$

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    Your second and third expressions should have an "$=0$" in there, but yes.2012-06-19
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    Strictly, you want $(W-1)(W-7)=0$ [same for second line too] so that $W=1$ or $W=7$. The easiest way to check you haven't made a mistake is by substituting these values into the original equation and checking that they work.2012-06-19
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    Omission of $=0$ is a frequent fault.2012-06-19
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    @MichaelHardy: The OP just meant to check if the simplification is correct. I don't see any frequent faults.2012-06-19
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    @Gigili : I didn't mean frequent in this posting; I meant frequent out there in the world. Zillions of students make this same mistake. I think they think what they're doing is pushing symbols around according to prescribed rules, as in long division, rather than at each step making a statement that should be true.2012-06-19
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    @MichaelHardy: Umm, no idea about the real world, never have been there! Yes, you're quite right.2012-06-19

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