Question

Teorema de Pitágoras, não consigo resolver nenhum desses.

Answer 1

a)

$a^2=b^2+c^2\\20^2=(3x)^2+(4x)^2\\400=9x^2+16x^2\\25x^2=400\\x^2=16\\\boxed{x=4}$

b)

$a^2=b^2+c^2\\(3\sqrt{5})^2=6^2+x^2\\9\cdot5=36+x^2\\x^2=40-36\\x^2=4\\\boxed{x=2}$

c)

$a^2=b^2+c^2\\(x+1)^2=(\sqrt{7})^2+x^2\\x^2+x+x+1=7+x^2\\2x+1=7\\2x=6\\\boxed{x=3}$

d)

$a^2=b^2+c^2\\(3\sqrt{2})^2=x^2+x^2\\9\cdot2=2x^2\\2x^2=18\\x^2=9\\\boxed{x=3}$

Bons estudos!