Respuesta:
[tex]x=2+\sqrt{6},\:x=2-\sqrt{6}[/tex]
Explicación paso a paso:
[tex]\frac{x\left(10x-40\right)}{2}=10\frac{x\left(10x-40\right)}{2}\cdot \:2=10\cdot \:2x\left(10x-40\right)=2010x^2-40x-20=20-2010x^2-40x-20=0x_{1,\:2}=\frac{-\left(-40\right)\pm \sqrt{\left(-40\right)^2-4\cdot \:10\left(-20\right)}}{2\cdot \:10}x_{1,\:2}=\frac{-\left(-40\right)\pm \:20\sqrt{6}}{2\cdot \:10}x_1=\frac{-\left(-40\right)+20\sqrt{6}}{2\cdot \:10},\:x_2=\frac{-\left(-40\right)-20\sqrt{6}}{2\cdot \:10}x=2+\sqrt{6},\:x=2-\sqrt{6}[/tex]
