Question

aplique uma razão trigonometria para determinar o valor da letra em cada caso​

Answer 1

$\large\boxed{\begin{array}{l}\sf cos(30^\circ)=\dfrac{5}{y}\\\sf\dfrac{\sqrt{3}}{2}=\dfrac{5}{y}\\\sf \sqrt{3}y=10\\\sf y=\dfrac{10}{\sqrt{3}}\cdot\dfrac{\sqrt{3}}{\sqrt{3}}\\\sf y=\dfrac{10\sqrt{3}}{\sqrt{3^{\diagdown\!\!\!\!2}}}\\\sf y=\dfrac{10\sqrt{3}}{3}\end{array}}$