Math test tomorrow. Roots. plz answear fast.

Sry not 3 its 2

How does this work (sqrt(2)-sqrt(8))^2 ?? plz expalain. why doesnt it become -6 or 6 and why is the answear 3??? ty for the answear in before hand

sqr8 = sqrt(4*2) = sqrt4 * sqrt2 = 2sqrt2

sqrt2 - 2sqrt2 = -sqrt2

(-sqrt2) ² = (-sqrt2)*(-sqrt2) = +2