Question

3x²=10,8
Va rog mult

Answer 1

$3 {x}^{2} = 10.8$

$3 {x}^{2} = \frac{108}{10}$

$3 {x}^{2} = \frac{54}{5}$

${x}^{2} = \frac{54}{5} \div 3$

${x}^{2} = \frac{54}{5} \times \frac{1}{3}$

${x}^{2} = \frac{54}{15}$

${x}^{2} = \frac{18}{5}$

$x = \pm \sqrt{ \frac{18}{5} }$

$x = \pm \frac{ \sqrt{18} }{ \sqrt{5} }$

$x = \pm \frac{3 \sqrt{2} \times \sqrt{5} }{5}$

$x =\pm \frac{3 \sqrt{10} }{5}$