The height of an equilateral triangle is 15 cm. The area of the triangle is?
Answer & explanation
Correct answer: option 2
AD the height of triangle = \(\frac{\sqrt {3}}{2}\) × side
⇒ 15 =\(\frac{\sqrt {3}}{2}\) a
⇒ a = 10\(\sqrt {3}\)
Area \(\frac{\sqrt {3}}{4}\) a2
= \(\frac{\sqrt {3}}{4} \times (10 \sqrt {3})^2\) = \(75 \sqrt {3}\)