Geometrymedium · Past Paper

What is the length of the altitude of an equilateral triangle with side 'a'?

Aa/2
B(sqrt(3)/2) * a
C(sqrt(3)/4) * a
Dsqrt(2) * a

✓ Correct Answer: B — (sqrt(3)/2) * a

Using Pythagoras on half the equilateral triangle: h^2 + (a/2)^2 = a^2 => h = (sqrt(3)/2)a.

Share this question

More from Geometry