Question

calcule a área do seguinte triângulo​

Answer 1

$a=5\sqrt{3}\ cm,\ b=4\ cm,\ \hat{C}=60\º\ \therefore\ \sin{\hat{C}}=\dfrac{\sqrt{3}}{2}\\\\\ \boxed{A=\dfrac{1}{2}ab\sin{\hat{C}}}\ \therefore\ A=\dfrac{1}{2}(5\sqrt{3})(4)\bigg(\dfrac{\sqrt{3}}{2}\bigg)\ \therefore\ \boxed{A=15\ cm^2}$