GeoGebra Classroom

# Isosceles Trapezoid - Definitions and Constructions

***************************************************************************** Our minimal definition: Isosceles trapezoid - a trapezoid with congruent base angles. ***************************************************************************** Construct an isosceles trapezoid. Then observe other constructions and answer the questions below.

What is the definition of isosceles trapezoid on which your construction is based?

## Other constructions of isosceles trapezoid

If you want to follow the construction steps, use the navigation buttons at the bottom to scroll through the steps. If you want to see the description/definition of an object, right click it (control+click on Mac).

## Construction 1:

C1: What is the definition used in this construction?

## Construction 2:

C2. What is the definition used in this construction?

## Construction 3:

This is a "reverse" question. Given the definition below, decide if it is a valid definition of an isosceles trapezoid, equivalent to our minimal definiton. You may want to construct it strictly from the definition and then play with your construction to formulate your conclusion. ******************************************************************************************************** We will call the pair of sides that are required to be parallel by the trapezoid definiton bases of the trapezoid. We will call the other two sides (that may or may not be parallel) legs. Definition: Isosceles trapezoid is a trapezoid with congruent legs. ********************************************************************************************************

Is this a valid definiton of an isosceles trapezoid equivalent to our minimal definition?

## Construction 4:

This is a "reverse" question. Given the definition below, decide if it is a valid definition of an isosceles trapezoid, equivalent to our minimal definiton. You may want to construct it strictly from the definition and then play with your construction to formulate your conclusion. ******************************************************************************************************** A trapezoid with congruent diagonals. ********************************************************************************************************