Question

Each side of an equilateral triangle is 10 cm long. The height of the triangle is
(a) $10\sqrt{3}\mathrm{cm}$
(b) $5\sqrt{3}\mathrm{cm}$
(c) $10\sqrt{2}\mathrm{cm}$
(d) 5 cm

Answer 1

(b) $5\sqrt{3}\mathrm{cm}$
$$\begin{gathered} \mathrm{Height}\mathrm{of}\mathrm{equilateral}\mathrm{triangle}=\frac{\sqrt{3}}{2}\times \mathrm{Side} \\ =\frac{\sqrt{3}}{2}\times 10 \\ =5\sqrt{3}\mathrm{cm} \end{gathered}$$