Question

Qual o perímetro do triângulo ABC
a) 22
b) 24
c) 26
d) 28
e) 30

Answer 1

$\large\boxed{\begin{array}{l}\rm b^2=8^2+10^2-2\cdot8\cdot10\cdot cos(50^\circ) \\\rm x^2=64+100-160\cdot0,64\\\rm x^2=164-102,4\\\rm x^2=61,6\\\rm x=\sqrt{61,6}\\\rm x=7,84\\\rm p=10+8+7,84=25,84\\\rm p\approxeq26\\\huge\boxed{\boxed{\boxed{\boxed{\rm\dagger\red{\maltese}~\blue{alternativa~c}}}}}\end{array}}$