G.CO.9 Proving Vertical Angles
Rigid Transformations (or Motions) - Examples: rotation, reflection, or translation (turn, flip or slide)
After one or more of these transformations, shapes still have the same size, area, angles and line lengths.
View the next two Geogebra examples and complete the following.
Come up with two transformations from one vertical angle to its partner.
Transformation #1
A ____(insert angle measure)______ degree _____(insert transformation)_____ around vertex B, creates a pair of vertical angles.
Use your knowledge of rigid transformations to explain what you can conclude about the measurement of a pair of vertical angles.
Transformation #2
3. Following your investigation above complete the sentence frame below:
A _____(insert transformation)_____ across a line passing through the vertex, creates a pair of vertical angles.
A _____(insert transformation)_____ across a line passing through the vertex, creates a pair of vertical angles.
Use your knowledge of rigid transformations to explain what you can conclude about the measurement of a pair of vertical angles.
What do you notice about the measures of the RED angles and the BLUE angles? Why is this the case?