A tetrahedron has :a)3 equilateral trianglesb)4 equilateral trianglesc...
A tetrahedron is a three-dimensional figure that consists of four triangular faces. Each face of a tetrahedron is an equilateral triangle, meaning that all three sides of the triangle are equal in length.
Let's break down the options given and determine the correct answer:
a) 3 equilateral triangles: If a tetrahedron had only three equilateral triangles, it would mean that one face is missing. However, a tetrahedron has four faces, so this option is incorrect.
b) 4 equilateral triangles: This option is correct. A tetrahedron has four equilateral triangles as its faces. Each triangle shares a common vertex with the other three triangles, forming a pyramid-like structure.
c) 5 equilateral triangles: If a tetrahedron had five equilateral triangles, it would mean that there is an additional face. However, as mentioned earlier, a tetrahedron only has four faces, so this option is incorrect.
d) 4 isosceles triangles: An isosceles triangle has two sides of equal length, but the remaining side is of a different length. Since a tetrahedron consists of equilateral triangles, all sides of each triangle are equal in length. Therefore, this option is incorrect.
In conclusion, a tetrahedron has four equilateral triangles as its faces, making option 'B' the correct answer.
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