find the missing side of the triangle plz help me and explain plz bc I don't understand

Answer:
√8
Step-by-step explanation:
Pythagorean's Theorem says 2^2+2^2=4+4=8.
Answer:
So we know that this is a right isosceles triangle because 2 sides are equal and there's a 90 degree angle,
In an isosceles right triangle, the sides are in the ratio 1:1:[tex]\sqrt{2}[/tex]
a^2 + b^2 = c^2
We use the Pythagorean Theorem, where a and b are the legs and c is the hypotenuse.
2(2^2)=c^2
c=2[tex]\sqrt{2}[/tex]