The length of \(AB\) & \(BC\) are 6. This is because the hypotenuse of a right-isosceles triangle is \(\frac{h}{\sqrt{2}}.\)
From this, you know that \(AB\Xi BC\) and the values are \(\frac{6\sqrt{2}}{\sqrt{2}} = 6.\)
If AB is 6, then 6 is the side of a 30-60-90 triangle or a half-cut equilateral triangle. This would mean that x is half of 6 or x is 3.
I had to write my answer in multiple posts since LaTeX hates me right now. I might be wrong so make sure to double check my work. Good Luck!
\(AB=BC \qquad\text{ABC is a right angled isosceles triangle}\\ 2*(AB)^2=(6\sqrt2)^2\\ 2*(AB)^2=72\\ (AB)^2=36\\ AB=BC=6\)
\(cos 60=\frac{1}{2}\)
\(\frac{x}{6}=\frac{1}{2}\\ x=3 \)
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