2D and 3D Shapes — Answer Key
Part A: Fill in the Blank
Write the missing word or number on each line.
1. A triangle has 3 sides.
A triangle is a 2D shape with exactly 3 sides.
2. A square has 4 corners.
A square has 4 corners, one at each point where two sides meet.
3. A circle has 0 sides.
A circle is a round shape with no straight sides.
4. A hexagon has 6 sides.
A hexagon is a 2D shape with exactly 6 sides.
5. A shape with 4 equal sides is called a square.
A square is the only common shape where all 4 sides are the same length.
6. A sphere has 0 flat faces.
A sphere is completely round with no flat faces at all.
7. A cube has 6 flat faces.
A cube is a 3D shape with 6 square flat faces.
8. A rectangle has 4 sides.
A rectangle is a 2D shape with 4 sides: 2 long sides and 2 short sides.
Part B: True or False?
Circle True or False for each statement.
1. A triangle has 3 corners.
True False
True — a triangle has 3 corners, one at each point where two sides meet.
2. A circle has 2 sides.
True False
False — a circle has 0 sides because it is completely round with no straight edges.
3. A cube is a 3D shape.
True False
True — a cube is a 3D shape because it has length, width, and height.
4. A cone has 2 flat faces.
True False
False — a cone has only 1 flat face, which is the circular base.
5. A pentagon has 5 sides.
True False
True — a pentagon is a 2D shape with exactly 5 sides.