This is the concept of geometry, we are required to get the slant height of the pyramid which has been formed by equilateral triangles;
Here we shall use the pythagorean theorem;
c^2=a^2+b^2
the slant side is the height of the pyramid, the side length is one of the hypotenuse thus, hypotenuse=11 cm,
the length of the slant height will be:
11^2=(11/2)^2+b^2
b^2=121-(11/2)^2
b^2=90.75
thus;
b=sqrt(90.75)
b=9.53 cm
The answer is, slant height will be 9.53 cm
