Question

6²= x²+ x² teorema de Pitágoras

Answer 1

$6^2= x^{2} + x^{2} \to\\\\ 36= 2 x^{2} \to\\\\ \dfrac{36}{2} = x^{2} \to\\\\ 18= x^{2} \to\\\\x= \sqrt{18}\to\\\\ \boxed{x=3 \sqrt{2} }$

Answer 2

6² = x² + x²
36 = 2x² (:2)
18 = x²
x² = 18
x = √18
x = √9.√2
x = 3√2
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18: 2
9: 3
3: 3
1      = 2.3² = √2.√9 = √2.3 = 3√2