√(x-√2)^2+∣(x+y-1)∣=0
√(x-√2)^2=0
x=√2
∣(x+y-1)∣=0
∣(√2+y-1)∣=0
y=1-√2
x^2-x(y-1)
=(√2)^2-√2[1-√2-1]
=2-√2*(-√2)
=2+2
=4