Step 1: Understanding the properties of an equilateral triangle.
In an equilateral triangle, all sides are equal, and all angles are \( 60^\circ \). The altitude of an equilateral triangle divides the triangle into two congruent 30-60-90 right triangles.
Step 2: Formula for the altitude in an equilateral triangle.
For an equilateral triangle with side length \( s \), the altitude \( h \) is given by:
\[
h = \frac{\sqrt{3}}{2} \times s
\]
Step 3: Applying the given side length.
Here, the side length of the triangle is \( 2a \). Therefore, the altitude is:
\[
h = \frac{\sqrt{3}}{2} \times 2a = a\sqrt{3}
\]
Step 4: Conclusion.
Therefore, the length of each altitude is \( a\sqrt{3} \).