Question

X ao quadrado igual a 6 ao quadrado mais 9 ao quadrado

Answer 1

${x}^{2} = {6}^{2} + {9}^{2} \\ {x}^{2} = 36 + 81 \\ {x}^{2} = 117 \\ x = \sqrt{117} = \sqrt{9 \times 13} \\ x = 3 \sqrt{13}$

Answer 2

$x^2=6^2+9^2\\x^2=36+81\\x^2=117\\x=\pm\sqrt{117}\\x=\pm\sqrt{9\cdot13}\\\boxed{x'=3\sqrt{13}}\\\boxed{x''=-3\sqrt{13}}\\ \\\\S=\{3\sqrt{13},\;-3\sqrt{13}}\}$

Bons estudos!