Question

Find the altitude of an equilateral triangle of side 10 cm.

Answer 1

Given an equilateral triangle of side $10cm$.

Altitude of an equilateral triangle is also a median

If all sides are equal, then $\frac{1}{2}$ of one side is $5cm$.

$\Rightarrow {10}^2-5^2=a^2$

$\therefore a=5\sqrt{3}$