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Rotation. Reflection. ???. I perched on the bow and travelled further. No, I perched on the stern and went further. a CM. a CM. A. A. P. B. B. D. D. C. C. G. G. P. E. E. F. F. Q. Q. a CM. a CM.
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Rotation Reflection ???
I perched on the bow and travelled further No, I perched on the stern and went further
A A P B B D D C C G G P E E F F Q Q aCM aCM
On the graph all the points move in a certain direction and move the same distance. This is called Translation. After the shape is moved it maintains a constant and shape and size. Can you give some examples of translational movements in life?
Title: Translation Copy and complete in your book: After an image is translated, the _________ between the ______________ points are equal. The ______ of the corresponding line segments are equaland the _______ corresponding angles are equal distance corresponding length size shape After the translation the______ and _______ are constant. size
A A P ’ B B ’ D D C C G G P ’ ’ E E F F Q ’ ’ ’ ’ ’ Q ∠CAB and ∠C’A‘B’ are called corresponding angles Point A and point A' are called corresponding points. Line segment AB and line segment A'B' are called corresponding line segments
On your whiteboards: Translation changes…（ ） A ShapeB Position C SizeD Shape, position and size B
On your whiteboards: A D B C F E
On your whiteboards: In the following 6 patterns which of patterns is a translation of image 1? • 1、如图，∠DEF是∠ABC经过平移得到的, ∠ABC=33°,求∠DEF的度数. （３）
On your whiteboards: The four small triangles in the figure are all equilateral triangles with a side length of 2 cm. Which triangles are translations of △ABC? △ECD △FAE Translating△ABCgetsand ______
On your whiteboards: Total area = area 1 + area 2 = area of EFCD = 1cm2
Your Turn: Using Translation A square rice field with a side length of 101m has two channels in both sides, each with a width of 0.5m What is the area planted in each rice field? Show all of your calculations.
Can you explain this method? (101-0.5×2)2 =1002 =10000 m2
Summary • Concept of translation • Nature of translation Moving all the points of a shape the same distance in a certain direction is referred to as translation. After the shape is translated, the distance between the corresponding points is equal, the length of the corresponding to the line segment are equal and the corresponding angle are equal in size. After the image is translated, the size of the image is unchanged and the shape of the image is unchanged.