a square
There can be no closed 3D shape with only one square and 3 triangles.
square based prism?
A square-based pyramid.
pyramid
a square
There can be no closed 3D shape with only one square and 3 triangles.
square based prism?
triangle and square 4 triangles one square
a hexagon * * * * * Depending on the shape and sizes of the triangles and where they are attached, you can also get a kite, a rectangle, a parallelogram, a decagon, octagon, pentagon.
A Triangular Pyramid has 4 triangles and 1 square.
Square-based pyramid.
A square-based pyramid.
A square and rectangle both have congruent triangles in them.
If you have 2 EQUILATERAL triangles, and you stack them on their respective hypotenuses, the result: SQUARE. If you have 2 ISOSCELES triangles, and you stack them on their respective hypotenuses, the result: RECTANGLE. If you have 2 OBTUSE triangles, and you stack them on their respective hypotenuses, the result: PARALLELOGRAM.
pyramid
Square pyramid