A property of triangles<span> that states that if the side lengths of a </span>triangle<span> are fixed, the </span>triangle can have only one shape.The triangle is the strongest shape due to the rigidity of its sides, which allows them to transfer force more evenly through their sides than other shapes.<span> Triangles are used extensively in the construction of buildings and bridges.</span><span> triangle cannot be deformed without changing its joints</span>
