Question

$30 {} ^{2} = 5 { }^{2} + x {}^{2}$

Answer 1

$30^{2} =5^{2} +x^{2} \\ \\ x^{2} =30^{2} -5^{2} \\ \\ x^{2} =900-25\\ \\ x^{2} =875\\ \\ x=\sqrt{875} =29,58~~~~aproximadamente$