I hope this helps you
9-9-9square root of 2
9square root of 2-9 square root of 2
x=square root of 2×9 square root of 2
x=18
x-x-x square root of 2
x square root of 2-x square root of 2
5square root of 2=square root of 2× x square root of 2
x=5 square root of 2/2
