A square-based pyramid.
There can be no closed 3D shape with only one square and 3 triangles.
square-based pyramid
pyramid
A square pyramid is one that has a square base. This means there are four triangles, one triangle on each side of the square base.
the bottom one is a square and the other 4 are triangles
There can be no closed 3D shape with only one square and 3 triangles.
triangle and square 4 triangles one square
One square and four triangles.
a pyramid
pyramid
A square pyramid has.
square-based pyramid
a square pyramid
A square pyramid is one that has a square base. This means there are four triangles, one triangle on each side of the square base.
the bottom one is a square and the other 4 are triangles
A shape formed by four triangles would have to be a tetrahedron. But I believe that a tetrahedron can have at most three right angled triangles. One with four of them is, I think, impossible.
To find four equilateral triangles connected to a square, start by drawing a square. Then, attach one equilateral triangle to each side of the square, ensuring that each triangle shares a side with the square. The vertices of the triangles should meet at the corners of the square. This arrangement will create a geometric figure with four equilateral triangles surrounding the square.