\(\sqrt{x^2-2x-8}=\sqrt{3}.\left(x-4\right)\)
\(\sqrt{x^2-2x-8}=\sqrt{3}x-4\sqrt{3}\)
\(x^2-2x-8=3x^2-24x+48\)
\(x^2-2x-8-3x^2+24x+48=0\)
\(-2x^2-11x+28=0\)
\(x=\dfrac{-\left(-11\right)\pm\sqrt{\left(-11\right)^2-4.1}.28}{2.1}\)
\(x=\dfrac{11\pm\sqrt{9}}{2}\)
\(x=\dfrac{11\pm3}{2}\)
\(x=\dfrac{11+3}{2}\Leftrightarrow x=7\)
\(x=\dfrac{11-3}{2}\Leftrightarrow x=4\)
\(\sqrt{7^2-2.7-8}=\sqrt{3}.\left(7-4\right)\)
\(\sqrt{4x^2-2.4-8}=\sqrt{3}.\left(4-4\right)\)
x1=7
x2=4
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