Shapes
A closed two-dimensional (flat) shape with 3 or more sides.
Polygon
An angle smaller than a right angle.
Acute angle
Two lines that are always the same distance apart.
The property of a shape that can be folded so that the two halves match exactly.
A two-dimensional (flat) polygon with 4 sides.
Quadrilateral
An angle larger than a right angle.
Two lines that cross each other forming a right angle.
A line that divides a shape into two mirror images.
The point at which the sides of a two-dimensional shape connect.
A quadrilateral with exactly 1 pair of parallel sides.
Trapezoid
An angle that is a corner.
A quadrilateral with 4 congruent sides.
A quadrilateral with two pairs of parallel sides.
A quadrilateral with two pairs of parallel sides (a parallelogram) and 4 right angles.
A two-dimensional (flat) polygon with 4 angles.
Quadrangle
A special type of rhombus (4 congruent sides) and 4 right angles.