Question

Xradical2-radical8=5radical2

Answer 1

$x \sqrt{2} - \sqrt{8} = 5 \sqrt{2}$

$x \sqrt{2} - 2 \sqrt{2} = 5 \sqrt{2}$

$\sqrt{2} (x - 2) = 5 \sqrt{2} \: | \div \sqrt{2}$

$x - 2 = 5$

$x = 5 + 2$

$x = 7$