Question

√2x+√2 y = 1 ;√2x-√2y=7​

Answer 1

add both equations

u will get

$2 \sqrt{2} x = 8$

$\sqrt{2} x = 8 \div 2 \\ \sqrt{2} x = 4 \\ x = 4 \div \sqrt{2}$

substitute x in any equation u will get y