Answer
Find out the altitude of the equilateral triangle .
To proof
By using the trignometric identity.
As shown in the diagram
and putting the values of the angles , base and perpendicular
solving
As
put in the above
a = 4 × 3
a = 12 units
The length of the altitude of the equilateral triangle is 12 units .
Option (F) is correct .
Hence proved