Question

Find the length of the altitude of an equilateral triangle with side 6 cm.

Answer 1

In `triangle ADC`

`sin 60^@ = (AD)/(AC)`

`sqrt3/2 xx AC = AD`

`sqrt3/2 xx 6 = AD`

`3sqrt3` cm = AD

Answer 2

Altitude of equilateral triangle = `sqrt3/2 xx "side"`

`= sqrt3/2 xx 6 = 3sqrt3`cm