why is it that structures like electric towers make use of triangular shapes and not quadrilaterals?

We can explain this by these points :

1 ) we know in triangle we have one side less than any quadrilateral , So cost of tower is less , if we make triangle shape tower .

2 ) If we make quadrilateral shape tower , it will more area and by making triangle shape tower , we can solve this problem .

3 ) Structures like electric towers make use of triangular shapes and not quadrilaterals as the triangle is very rigid and hence a strong shape. When we push inward at any one vertex of the triangle the triangle does not get distorted.

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