Question

alguém pode me ajudar nessas duas questões de trigometria?

Answer 1

Resposta:

Explicação passo-a-passo:

2) Basta usa a Lei dos Cossenos

$x^{2}=7^{2}+10^{2}-2.7.10.cos57\\\\\\x^{2}=49+100-140.0,54\\\\\\x^{2}=149+75,6\\\\x^{2}=224,6\\\\x=\sqrt{224,6}\\\\x=14,98$

3)

$A=\dfrac{7.10.sen57}{2}\\\\\\A=\dfrac{70.0,84}{2}\\\\A=35.0,84\\\\A=29,4$