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Home > CCG > Chapter 2 > Lesson 2.1.1 > Problem 2-11


Jerry has an idea. Since he knows that an isosceles trapezoid has reflection symmetry, he reasons, “That means that it must have two pairs of angles with equal measure.” He marks this relationship on his diagram at right.

Copy the shapes below onto your paper. Similarly mark which angles must have equal measure due to reflection symmetry.  

Isosceles trapezoid with horizontal bases, has vertical dashed line in the middle, bottom left & bottom right angles, each marked with 1 tick mark, top left & top right angles each marked with 2 arcs.

  1. 4 sided polygon, with sides labeled as follows: left top & left bottom sides, 1 tick mark, right top & right bottom sides, 2 tick marks.

  1. Triangle with sides labeled as follows: left & right sides, 1 tick mark.

  1. Regular Hexagon

  1. Rhombus

Draw all lines of symmetry.

Mark the angles that correspond and are on opposite sides of the line of reflection.