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Sample Problems
8th Standards


Textbook
McDougal
Pre-Algebra


Self Help
On-Line Learning


Glossary
Holt MATH

TRANSFORMATIONS
CONGRUENT AND SIMILAR

CORE STANDARDS :
8.G.1 --- Verify physical models properties of rotations, reflections, translation; congruence and similarity.
8.G.2 --- Understand that a two-dimensional figure is congruent to another if the second can be obtained from the first by a sequence of rotations, reflections, and translations.
8.G.3 --- Effect of dilations, translations, rotations, and reflections on two-dimensional figures using coordinates
8.G.4 --- Shapes can be manipulated through a series of transformations and dilations so that one given shape can be mapped on to another given shape in order to prove similarity.

Link to OVERVIEW TRANSFORMATIONS
I. TRANSLATION slides each point of a figure the same distance in the same direction.
A. EVERYDAY examples... 1) exterior buildings 2) windows.
B. link to... COORDINATE examples
C. Interactive PRACTICE — TRANSLATIONS
II. REFLECTION flips a figure over a mirror or symmetry line.
A. EVERYDAY examples... 1) lake images 2) mirrors
B. link to... COORDINATE examples
C. Interactive PRACTICE — REFLECTIONS

III. ROTATION turns a figure about a fixed point at a given angle and a given direction.
A. EVERYDAY examples... 1) flower petals 2) Earth axis.
B. link to... COORDINATE examples
C. Interactive PRACTICE — ROTATIONS
D. Math Videos:
1---Video: Easy way to do a basic rotation using tracing paper (or clear plastic).
This rotation used (0,0) as the rotation point and rotated 90° clockwise.
2---Video: Understand point basics of ROTATION around the origin (0,0)

IV. DIALATION changes the size of an object, but not the shape.
A. EVERYDAY examples... 1) model cars 2) Barbie dolls
B. link to... COORDINATE examples
C. Math Videos:
1---Video #46339:
Dilation Examples in Real Life
2---Video #1357:
Prove two figures are similar after a dilation
3---Video #46130:
Determine whether the graph represents a dilation.
4---Video #1357:
Two figures are SIMILAR after a Dilation.

More Math Lessons:

Video: Two figures are SIMILAR or CONGUENT after a TRANSFORMATION.
Video: Prove two figures are CONGRUENT after a series of REFLECTION or ROTATION or DILATION.
Video: How to move figures translation, rotation, reflection (point by point)