What is x (using pythagorean theorem)? and how to do it

Pythagorean Theorem= a^2+b^2=c^2
By looking at the shape, it seems like an isosceles triangle. Meaning the two legs of the triangle must be congruent.  
Therefore,  a^2+b^2=6^2
a^2+b^2=36
A number plus itself that equals 36 is 18
Thus, 18+18=36
Now all we have to do is square root the the equation to get the final answer(s)
√18+18=36
4.24^2+4.24^2=6^2 would be the final equation making 4.24 your final answer.
Hope this helped! :)

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