Question

The height of an equilateral triangle is 18 cm. Its area is

• A. $$36\sqrt{3}sq.cm$$
• B. $$108\sqrt{3}sq.cm$$
• C. 108 sq.cm
• D. $$96\sqrt{3}sq.cm$$

Answer 1

Answer:

$$108\sqrt{3}sq.cm$$

Height of equilateral triangle $=\frac{\sqrt{3}}{2}\times{side}$

=>18=\frac{\sqrt{3}}{2}\times{side}

=>Side=\frac{18\times{2}}{\sqrt{3}}

$=12\sqrt{3}cm$

Area of triangle $=\frac{\sqrt{3}}{4}\times{side^2}$

$=\frac{\sqrt{3}}{4}\times({12\sqrt{3}})^2$

$=108\sqrt{3}cm^2$