In the ancient city of Marrakesh polygons are on display.

In this program we explore the properties of quadrilaterals. We do this in the context of two real-world applications. In the first, we explore the architecture of Frank Lloyd Wright as an application of squares and rectangles; in particular, we look at his Fallingwater house.

Stonehenge is best known as a circular structure. But it's the post and lintel construction used that is noteworthy, and this type of construction involves quadrilateral shapes.

Frank Lloyd Wright’s architectural masterpiece Falling Water is also a stunning assembly of quadrilateral shapes.

The Puerta de Europa towers in Madrid bring parallelograms front and center. These tilted towers, looking like modern-day towers of Pisa seem to defy gravity, but rely on the stability brought about by its quadrilateral structure.

In this program we explore the properties of triangle. We do this in the context of two real-world applications. In the first, we explore the triangular trusses in the Eiffel Tower and in the process learn about key properties of triangles.

The Bank of China building in Hong Kong is a dramatic example of triangular support. The notion of triangular trusses is introduced, along with the key concepts developed in the rest of the program.

The Eiffel Tower includes quite a number of exposed triangular trusses. The properties of triangles are used to explore and explain the frequent use of triangular trusses in many building. In particular, isosceles and equilateral triangular trusses are explored.

The ancient port city of Corinth in Greece allows us to explore the evolution of sailing. The shapes of sails went from rectangular to triangular. The use of right-triangle-shaped sails changed the nature of sailing.

The Bank of China building in Hong Kong is a dramatic example of triangular support. The notion of triangular trusses is introduced, along with the key concepts developed in the rest of the program.

In this Google Earth Voyager Story, explore the geometry of quadrilaterals in the context of architecture.

In this Google Earth Voyager Story, explore the geometry of quadrilaterals in the context of architecture.

In this Slide Show, we show how to construct the perpendicular bisectors of the three sides of a triangle to show they intersect at a single point. This presentation requires the use of the TI-Nspire iPad App. Note: the download is a PPT.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

This collection of clip art images includes image sequences for key topics in geometry This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.