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Let's say you have

$0.5\times 1.5 \ x^2 - (0.5\times 3.2 \times 1.5) = 23 $

or something similar. Is there an easy way to just get $x^2$ in one step?

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    @ZafarS I don't think I'm the only one that is surprised by the up-vote on this question. I am also surprised at your swift defense of it. The question is elementary (even by the standard of the other questions you have asked in the past), does not show any useful research and there is no attempt at the answer. An up-vote in this case (I'm sorry to say) just doesn't appear to be warranted.2012-11-05

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If $a \times x^2 - b = c$ then $x^2 = {c+b\over a}$ There is really no easier way to find $x^2$ than just computing the value of this expression. In your case, $a = 0.5\times 1.5=0.75$, $b=0.5\times 3.2\times 1.5=2.4$, and $c=23$.

Sometimes you can save time by cancelling common factors first, but that is not the case here, since $c=23$ has no nice factor in common with $b$.

By the way, you are using both decimal commas and decimal points. It's better not to mix different notations.

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One moves expressions around in his head. Performing mental gymnastics, we have $x^2=\frac{23+0.5\times 3.2\times 1.5}{0.5\times 1.5}$.