Answer :
Assuming it’s a equilateral triangle the answer is 8sqrt(3)
Height 12cm
Cut the triangle in half so it becomes a 30-60-90 triangle
So 12/sqrt(3)=x and the side you want is 2x so it is 24/sqrt(3) for each side but you need to make sure you simplify it to (24sqrt(3))/3 and then one more time to 8sqrt(3)