a) Label the vertices of the image

# Key Vocabulary

clockwise

- To identify \(A’\): Which vertex will make \(m \angle AOA’\) = \(90°\)? Use the same way to determine \(B’,\; C’\) and \(D’\) \((m \angle BOB’\) = \(90°\), \(m \angle COC’\) = \(90°\) and \(m \angle DOD’\) = \(90°\)
- \(A’\) is shown below.
- To find lengths of sides and measures: Since the \(2\) trapezoids are identical (congruent), the length of the matching (corresponding) sides and angle measures are equal.
- \(AD\; =\; A’D’ ,\; m \angle A \;=\; m \angle A’\)