Section 12-7 Dilations SPI 32D: determine whether the plane figure has been dilated given a diagram and vice versa

View again

All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
PDF
6 pages
0 downs
3 views
Share
Description
Section 12-7 Dilations SPI 32D: determine whether the plane figure has been dilated given a diagram and vice versa. Objectives: Locate dilation images of figures. Vocabulary. Scale Factor describes the size change from original figure to image Dilation
Transcript
Section 12-7 DilationsSPI 32D: determine whether the plane figure has been dilated given a diagram and vice versa
• Objectives:
• Locate dilation images of figures
• Vocabulary
• Scale Factor
• describes the size change from original figure to image
• Dilation
• transformation whose preimage and image are similar
• has a center
• scale factor greater than zero
• For any point R, R’ is on CR and CR’ = n · CRDilationIn general, a dilation with center C and scale factor n, is a transformation for which the following are true:
• the image of C is itself (C = C’)
• n · CRR’RC = C’ (Center)EnlargementsEnlargementsDilation is an enlargement if the scale factor is > 1.B’C’The diagram is an enlargement with a scale factor of 2.imageBC42preimageA’ = A (Center)DD’ReductionsReductionsDilation is a reduction if the scale factor is between 0 and 1.FGF’G’The diagram is a reduction with center C and a scale factor of ¼ .image.CE’H’EHFinding Scale FactorsCircle A with 3-cm diameter and center C is a dilation of concentric circle B with 8-cm diameter. Describe the dilation.The circles are concentric, so the dilation has center C. Because the diameter of the dilation image is smaller, the dilation is a reduction. diameter of dilation imagediameter of preimage38=scale factor:38The dilation is a reduction with center C and scale factor . 1 200The floor plan is a reduction of the actual dimensions by a scale factor of . Real-World and DilationsThe scale factor on a museum’s floor plan is 1 : 200. The length and width on the drawing are 8 in. and 6 in. Find the actual dimensions in feet and inches.Multiply each dimension on the drawing by 200 to find the actual dimensions. Then write the dimensions in feet and inches.8 in. X 200 = 1600 in. = 133 ft, 4 in.6 in. X 200 = 1200 in. = 100 ftThe museum floor measures 133 ft, 4 in. by 100 ft.
Related Search
Similar documents

Determine whether the triangles are similar. If so, write a similarity statement

View more... 