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The equation is $\"\"$ . \ \ $\"\"$ (Square each side and eliminate the square roots)

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$\"\"$ (Subtract 12 from each side)

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$\"\"$ (Divide each side by 3) \ \

$\"\"$

Check:

To check the solution substitute $\"\"$ in $\"\"$ .

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$\"\"$ (Evaluate square roots: $\"\"$ )

The solution is "True". $\"\"$

The solution is "True".