Lines
This is a straight path that goes on forever in both directions.
What is a line?
This is formed when two lines meet at a vertex or point.
What is an angle?
A shape with three straight sides and three angles.
What is a triangle?
When you fold a shape and both sides match exactly, it has this.
What is symmetry?
The point where two lines meet.
What is a vertex?
This part of a line has two endpoints and does not go on forever.
What is a line segment?
An angle that measures exactly 90 degrees.
What is a right angle?
A shape with four equal sides and four right angles.
What is a square?
A square has how many lines of symmetry?
What is 4?
The distance around a 2D shape.
What is perimeter?
This starts at one endpoint and goes on forever in the other direction.
What is a ray?
An angle that measures less than 90 degrees.
What is an acute angle?
A four-sided shape with opposite sides equal but not necessarily all sides equal.
What is a rectangle?
A rectangle has how many lines of symmetry?
What is 2?
The space inside a 2D shape.
What is area?
These lines never cross and are always the same distance apart.
What are parallel lines?
An angle that measures more than 90 degrees but less than 180 degrees.
What is an obtuse angle?
A shape with all points the same distance from the center.
What is a circle?
A shape that has no symmetry is called this.
A polygon with 6 sides.
What is a hexagon?
These lines cross each other to form right angles.
What are perpendicular lines?
An angle that measures 180 degrees.
What is a straight angle?
A five-sided polygon.
What is a pentagon?
This shape has infinite lines of symmetry because it can be folded through its center in endless ways.
What is a circle?
Two angles that add up to 90 degrees.
What are complementary angles?