Question

10√28-7√63=x la 2....

Answer 1

$10 \sqrt{28} - 7 \sqrt{63} = {x}^{2}$

$20 \sqrt{7} - 21 \sqrt{7} = {x}^{2}$

$- \sqrt{7} = {x}^{2}$

$x = \sqrt[4]{7} \: \: sau \: - \sqrt[4]{7}$