Question

qual a medida do lado x?​

Answer 1

Resposta:

$\sin(45) = \frac{10}{x} \\ \frac{ \sqrt{2} }{2} = \frac{10}{x} \\ \frac{ \sqrt{2} }{2} x = 10 \\ x = \frac{10}{ \frac{ \sqrt{2} }{2} } \\ x = 10 \times \frac{2}{ \sqrt{2} } \\ x = \frac{20}{ \sqrt{2} } \\ x = \frac{20 \sqrt{2} }{2} \\ x = 10 \sqrt{2}$

logo a alternativa correta é (A)