Question

Utilizando o teorema de pitagoras, determine o valor de x nos triangullos retangulos

Answer 1

20²=(3x)² + (4x)²
400=9x² + 16x²
400=25x²
400/25=x²
x=$\sqrt{400/25}$
x=20/5
x=4

(3√5)²= 6² + x²
9.5=36 + x²
45-36= x²
9=x²
x=√9
x=3

Answer 2

a)

$20^2 = (3x)^2+(4x)^2$

$400 = 9x^2 + 16x^2$

$25x^2 = 400$

$x^2= \frac{400}{25}$

$x^2 = 16$

$\boxed{x=\pm4}$

b)

$(3 \sqrt{5})^2 = x^2 + 6^2$

$9*5 = x^2 + 36$

$45 = x^2 + 36$

$x^2 = 45-36$

$x^2 = 9$

$\boxed{x = \pm3}$

Espero ter ajudado. :))