Question

solve for x and y, x+√y=7 and √x+y=11

Answer 1

sorry I'm not sure
I can't understand your given step

Answer 2

√x+y=7

x+√y=11

√x=7-y

√y=11-x

the square root of a number is always the positive square root

therefore y can't be greater than 7 and x can't be greater than 11

look at the perfect squares 1, 4, 9, 16

assuming x and y are perfect squares and a little trial and error...

x=9 and y=4