Question

a medida de x na figura é​

Answer 1

Neste caso aplicamos a lei dos cossenos:

$x^2=4^2+6^2-2.4.6.cos(120\º)$

$x^2=16+36-2.4.6.(-\frac{1}{2})$

$x^2=52-48.(-\frac{1}{2})$

$x^2=52+24$

$x^2=76$

$x=\sqrt{76}$

$x=\sqrt{4.19}$

$x=2\sqrt{19}$