Geometry: Perpendicular Sides and Shapes

Perpendicular Sides

• Perpendicular means two lines or sides that meet at a right angle (90 degrees).
• Perpendicular sides are common in real-life situations, such as houses, storage boxes, and rectangles.
• A special symbol (a box in the corner angle) is used to signify that two sides are perpendicular without measuring.

Shapes with Perpendicular Sides

• The most common shapes with perpendicular sides are squares, rectangles, and right triangles.
• A quadrilateral is a shape with four sides, and if all its angles are equal, then the sides are perpendicular.
• Open shapes, like a box without a top, can also have perpendicular sides.

Real-World Examples of Perpendicular Sides

• Cracker boxes, thresholds of doors, and notebooks have perpendicular sides.
• Roads that intersect at a right angle are also perpendicular.

Perpendicular Line Segments

• A line segment is a line that begins and stops at a point.
• Perpendicular line segments are line segments that intersect at a 90-degree angle.
• If two line segments intersect at a 90-degree angle, all four angles between them are also 90 degrees.

Perpendicular Shapes

• A perpendicular shape is a shape with at least two sides that come together at a 90-degree angle.
• Examples of perpendicular shapes include squares, rectangles, right triangles, cubes, and rectangular prisms.
• These shapes can be easily identified by the presence of a box symbol in the angle, indicating a 90-degree angle.

Shapes with Perpendicular Lines

• A cube has perpendicular sides as well as perpendicular faces.
• A right trapezoid has a pair of parallel sides and sides that are perpendicular to each other.
• The presence of a box symbol in the angle indicates a 90-degree angle and perpendicular sides.

Learn about perpendicular sides, their real-life applications, and shapes that have them, including squares, rectangles, and right triangles.