Geometric Transformations Notes - Jackson County …€¦ · Geometric Transformations Notes 1...

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Geometric Transformations Notes 1 Advanced Math Mar 19:23 AM A translation is nothing more than a geometric transformation that slides each point in a figure the same distance in the same direction In this translation, ∆CDE is being translated to the right by the same length as segment AB. What do you think is true about ∆CDE and ∆C'D'E'? ∆CDE  ∆C'D'E' Mar 19:34 AM A figure can be translated in any direction and any distance. A car traveling down the road is a good example of a translation in action. The shape of the car is not being altered in any way, it is simply being moved from one point to another. Translation Example.gsp

Transcript of Geometric Transformations Notes - Jackson County …€¦ · Geometric Transformations Notes 1...

  • GeometricTransformationsNotes

    1

    AdvancedMath

    Mar19:23AM

    Atranslationisnothingmorethanageometrictransformationthatslideseachpointinafigurethesamedistanceinthesamedirection

    Inthistranslation,CDEisbeingtranslatedtotherightbythesamelengthassegmentAB.

    WhatdoyouthinkistrueaboutCDEandC'D'E'?

    CDEC'D'E'

    Mar19:34AM

    Afigurecanbetranslatedinanydirectionandanydistance.

    Acartravelingdowntheroadisagoodexampleofatranslationinaction.Theshapeofthecarisnotbeingalteredinanyway,itissimplybeingmovedfromonepointtoanother.

    TranslationExample.gsp

  • GeometricTransformationsNotes

    2

    AdvancedMath

    Aug87:45AM

    Translation means SLIDE

    Aug138:58AM

    TranslationRules

    *Totranslateafigureaunitstotheright,increasethexcoordinateofeachpointaunits.

    *Totranslateafigureaunitstotheleft,decreasethexcoordinateofeachpointaunits.

    *Totranslateafigureaunitsup,increasetheycoordinateofeachpointaunits.

    *Totranslateafigureaunitsdown,decreasetheycoordinateofeachpointaunits.

  • GeometricTransformationsNotes

    3

    AdvancedMath

    Mar110:27AM

    Areflectionisatransformationthatflipsafigureacrossalinetocreateit'simage.

    Anotherwaytothinkaboutitisthateachpointinareflectedimageisthesamedistanceawayfromthelineofreflectionastheoriginalpointwas.

    Whatistrueaboutafigureandit'sreflectedimage?

    Aug139:03AM

    ReflectionRule

    *Thereflectionofthepoint(a,b)acrossthexaxisisthepoint(a,b)

    *Thereflectionofthepoint(a,b)acrosstheyaxisisthepoint(a,b)

  • GeometricTransformationsNotes

    4

    AdvancedMath

    Mar110:32AM

    Rotationsareprobablythemostdifficulttypeofgeometrictransformationtounderstand.

    Arotationisatransformationthatturns,orspins,afigurearoundapoint.

    Mar111:43AM

    Afigurecanberotatedaroundapointonthefigureitself.

    Inthiscasethetrianglewasrotatedmultipletimesaroundacenterpointthatwasalsoonevertexofthetriangle.

    Orafigurecanberotatedaroundapointthatiscompletelyseparatefromthefigureitself

    Inthiscase,thesametrianglewasrotatedaroundapointseparatefromthetriangle.

  • GeometricTransformationsNotes

    5

    AdvancedMath

    Mar111:48AM

    Rotationsaregenerallymeasuredbytheangleofrotation.

    Thisfigurewouldrepresenta90orotationbecausetheanglecreatedbythecorrespondingverticesandthecenterofrotationisa90oangle.

    Thisfigurerepresentsa135orotationforthesamereason.

    90o

    135o

    RotationExample.gsp

    Aug138:50AM

    1)Therotationofthepoint(x,y)90degreesclockwiseabouttheorigin,isthepoint(y,x).

    2)Therotationofthepoint(x,y)180degreesclockwiseabouttheoriginisthepoint(x,y).

    3)Therotationofthepoint(x,y)90degreescounterclockwiseabouttheoriginisthepoint(y,x)

    RotationRules

  • GeometricTransformationsNotes

    6

    AdvancedMath

    Aug1311:31AM

    A

    B C

    D

    RotateFigureABCD90degreesand180degrees

    Aug1311:47AM

    Rotatethetriangle90degreesand180degreesusingtherule

  • GeometricTransformationsNotes

    7

    AdvancedMath

    Mar111:54AM

    Dilationsareatypeoftransformationduringwhichwegroworshrinkafigure.

    We'veactuallyalreadystudiedthistypeoftransformationquiteindepth?Doesanyonerememberwhen?

    ThemajorityofourStretchingandShrinkingunitwasdevotedtosimilarfigurescreatedbydilatingaplanefigure,soI'mnotgoingtospendalotoftimetalkingaboutthem.

    Mar18:02PM

    Dilationsareusuallymeasuredbytheirscalefactor.

    Reminder:Ascalefactorthatisgreaterthanonecreatesalargerimage.

    Ascalefactorbetween0and1createsasmallerfigure.

    ScaleFactor=3

    ScaleFactor=1/2

  • GeometricTransformationsNotes

    8

    AdvancedMath

    Aug138:55AM

    DilationRule

    Todilateafigurewithrespecttotheorigin,multiplythecoordinatesofeachofitspointsbythepercentofdilation.

    Mar19:17AM

    Therearefourbasictransformationsthatwewillbeconcernedwiththisyear.Talktothepeopleatyourableandtrytodefineeachoftheseinyourownwords

    Translation Reflection

    Rotation Dilation

  • GeometricTransformationsNotes

    9

    AdvancedMath

    Mar18:24PM

    Recap

    Translation Reflection

    Rotation Dilation

    Ashiftoraslidethatcreatesacongruentimage

    Aflipthatcreatesacongruentimage.

    Aspinorturnthatcreatesacongruentimage

    Growingorshrinkingafiguretocreateasimilarfigure.

    Mar18:07PM

    Inadditiontorecognizinganddescribingthese4basictranformations,therearealsosomerulesthatgovernhowtranslationsbehaveonacoordinategrid.ConsiderquadrilateralCDEFbelow.Whatarethecoordinatesofthe4vertices?

    (2,1)

    (4,2)

    (3,6)

    (2,4)

    WhatwouldhappentothosecoordinatesifItranslatedthefigure7unitstotheleft?

  • GeometricTransformationsNotes

    10

    AdvancedMath

    Mar18:17PM

    (2,1)

    (4,2)

    (3,6)

    (2,4)

    Iwouldhavetosubtract7fromthexvalueofeachcoordinatepair!

    (5,1)

    (3,2)

    (4,6)

    (5,4)

    Aug138:42AM

    Whatkindoftransformationarewedealingwith?Translation,Reflection,Rotation,orDilation

    A B

    CD

    A'

    B'C'

    D'

  • GeometricTransformationsNotes

    11

    AdvancedMath

    Aug138:42AM

    Whatkindoftransformationarewedealingwith?Translation,Reflection,Rotation,orDilation

    A B

    CD

    A' B'

    C'D'

    Aug138:42AM

    Whatkindoftransformationarewedealingwith?Translation,Reflection,Rotation,orDilation

    A B

    CD

    A' B'

    C'D'

  • GeometricTransformationsNotes

    12

    AdvancedMath

    Aug138:42AM

    Whatkindoftransformationarewedealingwith?Translation,Reflection,Rotation,orDilation

    A B

    CDA' B'

    C'D'

    Aug1412:08PM

    Doyouknowtherules?

    Horizontaltranslation:(x,y)=(xa,y)

    Verticaltranslation:(x,y)=(x,ya)

    Diagonaltranslation:(x,y)=(xa,ya)

    Reflectionaboutyaxis:(x,y)=(x,y)

    Reflectionaboutxaxis:(x,y)=(x,y)

    Rotation90degreesclockwise:(x,y)=(y,x)

    Rotation180degrees:(x,y)=(x,y)

    Rotation90degreescounterclockwise:(x,y)=(y,x)

    Dilationby.5:(x,y)=(x/2,y/2)

    Dilationby2:(x,y)=(x2,y2)

  • Attachments

    TranslationExample.gsp

    RotationExample.gsp

    SMART Notebook

    SMART Notebook

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