JAMB - Mathematics (2010 - No. 15)
If the area of ΔPQR above is 12\(\sqrt{3}\) cm\(^2\), find the value of q?
6 cm
7 cm
8 cm
5 cm
説明
Area of a triangle = \(\frac{1}{2}\) ab Sinθ
12\(\sqrt{3}\) = \(\frac{1}{2}\) x 8 x q sin 60
12\(\sqrt{3}\) = 4 x q x \(\frac{\sqrt{3}}{2}\)
12\(\sqrt{3}\) = 2q\(\sqrt{3}\)
q = \(\frac{12\sqrt{3}}{2\sqrt{3}}\)
q = 6cm.