TRIANGLES
A triangle with all angles less than 90° belongs to this category.
What is an acute triangle?
A quadrilateral with only one pair of parallel sides is called this.
What is a trapezoid?
This 3‑D figure has a circular base and one curved surface that comes to a point.
What is a cone?
A triangle with one angle greater than 90° is classified as this.
What is an obtuse triangle?
A quadrilateral with four right angles but not necessarily four equal sides is this shape.
What is a rectangle?
Name the 3‑D figure that has two identical circular bases and one curved surface.
What is a cylinder?
A triangle with all sides different lengths is called this.
What is a scalene triangle?
This quadrilateral has four equal sides and two pairs of parallel sides, but its angles are not required to be right angles.
What is a rhombus?
A solid with two triangular faces and three rectangular faces is classified as this.
What is a triangular prism?
Classify a triangle that has two equal sides and one right angle.
What is an isosceles right triangle?
A shape has opposite sides parallel and equal, but no right angles. Name the shape.
What is a parallelogram?
A shape has a square base and four triangular faces that meet at a point. Name it.
What is a square pyramid?
Explain why a triangle with side lengths 5 cm, 7 cm, and 5 cm fits into a specific category.
It is an isosceles triangle because it has two equal sides.
Explain why every square is also a rectangle, but not every rectangle is a square.
A square has four right angles and four equal sides, which fits the definition of a rectangle.
A rectangle may have different-length sides, so it cannot always be a square.
A 3‑D figure has 6 rectangular faces, 12 edges, and 8 vertices. Identify it.
What is a rectangular prism?