Example 3

Given the quadrilateral , the square , and the information that is the same distance from and , show that is symmetrical along segment .
  1. Recall the definition of line symmetry.
  2. Since and , is a line of symmetry for where .
  3. has the same area as because they share a base and have equal height. , so .
  4. We now know is a line of symmetry for and is a line of symmetry for , so and quadrilateral is symmetrical along .
This applet is provided by Walch Education as supplemental material for their mathematics programs. Visit www.walch.com for more information on their resources.