Ordered Pair: a pair of numbers where order is important, for example, (4,6) is different to (6,4); often used to indicate on a coordinate plane, graph or map
Coordinate Plane: a plane containing two perpendicular axes (x and y) intersecting at a point called the origin (0,0)
Two-Dimensional: a figure that can be measured in two directions, such as length and width
Angles: the figure formed when two rays or line segments share the same endpoint
Point: an exact position or location
Line: a straight path extending in both directions with no endpoints
LineSegment: a part of a line that includes two points, called endpoints, and all the points between them
PerpendicularLines: lines that intersect to form right angles
ParallelLines: lines in a plane that never intersect
Base: a side of a polygon or a face of a solid figure by which the figure is measured or named
Quadrilateral: a polygon with four sides
Parallelogram: a quadrilateral (4-sided figure) that has both pairs of opposite sides equal and parallel (Example: all rhombi, [plural for rhombus], squares and rectangles are parallelograms)
RegularPolygons: a polygon that has all equal sides or equal angles
IrregularPolygons: a polygon that does not have all equal sides or all equal angles
Rectangle: a quadrilateral with four right angles and two pairs of opposite equal parallel sides
Square: a quadrilateral with four equal sides and four right angles, opposite sides that are parallel, two diagonals that bisect at right angles, and four lines of symmetry
Triangle: a polygon with three angles and three sides
Rhombus: a parallelogram with four equal sides and equal opposite angles
Trapezoid: a quadrilateral with one pair of parallel sides
Geometry Activities
Name two-dimensional figures and find examples at home.
Draw different polygons within a piece of triangle grid paper, or use combinations of triangles to create other polygons.
Make flash cards of different geometric figures and their properties.
Identify, describe, and different household objects as two-dimensional figures.
Use a compass or a computer to draw geometric figures.