Postulates & Theorems - chapter 9 Flashcards
1
Q
A composition of two isometries is ….
A
an isometry. (theo. 9-4-1)
2
Q
The composition of two reflections across two parallel lines is equivalent to …. (a). The length of the translation vector is …. (b). The composition of two reflections across two intersecting lines is equivalent to …. (c). The angle of rotation is …. (d)
A
(a) a translation.
(b) twice the distance between the lines.
(c) a rotation.
(d) twice the measure of the angle formed by the lines.
(theo. 9-4-2)
3
Q
Any translation or rotation is equivalent to ….
A
a composition of two reflections. (theo. 9-4-3)
