9.5 Dilations. Brett Solberg AHS ‘11-’12. Warm-up. Draw all the lines of symmetry. What is the angle of rotation? 123. Today’s Agenda. Warm-up/HW Review Chapter 9 Review 9.5 Dilations Scale Factor enlargement reduction. Announcements. Today Review 9.5 Next Class - PowerPoint PPT Presentation
9.5 DilationsBrett Solberg AHS 11-12Warm-upDraw all the lines of symmetry. What is the angle of rotation?
Todays AgendaWarm-up/HW Review
Chapter 9 Review
9.5 DilationsScale Factorenlargement reduction
Homework Worksheet Packet9.2 Graphing PacketReview Worksheet
TransformationsTranslations (slide)rule of (4, -5)
Reflections (flip)x-axis(x, y) (x, -y)y-axis(x, y) (-x, y)line
RotationsCenter of Rotationprotractorcompass
Rotating about Origin90 clockwise (x, y) (y, -x)90 counterclockwise (x, y) (-y, x)180 either way (x, y) (-x, -y)
RotationRotate 90, 180, 270
SymmetryReflection Symmetrylines of symmetry
Rotational Symmetryangle of rotation
DilationA dilation is a transformation whose image and preimage are similar.
VocabularyScale Factor determines the size change from the original figure to its image.
The dilation is an if the scale factor is greater than 1.
The dilation is a if the scale factor is between 0 and 1. enlargementreductionExample 1Find the scale factor. The red square is the dilation of the blue square. 2244Example 3Scale Factor = 2
Example 2PointScale FactorImage(2, 3)3(6, 2)(-2, 0) 2(4, -1)1/3 (10, 15)20(-10, -20) 1/5Built in 1974, originally called the Sears tower.
Stands at 1451ft (442m)
Was the worlds tallest building for 25 years
Currently the tallest building in USA.Willis Tower
15The ratio of height to width is 6.45:1.
The building is 1451 ft tall. What is the width?Willis Tower
16Willis Tower LEGO Model (Sears Tower)
Willis Tower Scale Model18The ratio of height to width is 6.45:1 If the width of the model is 3 ft, and the model is similar to the actual tower, how tall is the model?Solving Proportions
19Jaguar ProportionActual Dimensionswidth 75 incheslength 189 inches
Model dimensionswidth 7 incheslength 20 inches
Does a dilation occur?
AssignmentsAssignmentsWorksheet Packet (50 points)9.2 Graphing Packet (10 points)Review Worksheet (10 Points)Warm-ups (10 points)Extra Credit Opportunitiespg 523 #1 - 29 Postertranslationreflectionrotationdilation