Evidence of Student Vocabulary Knowledge Skills Instructional Achievement Level Descriptors Attainment/Assessment Students: Dilations Students know: Students understand/are able EEG-SRT.1-3. N/A (See EEG-CO.6-8.) Given a center of dilation, a to: scale factor, and a polygonal Center Methods for finding the length of image, line segments (both in a coordinate Accurately create a new image Scale factor plane and through measurement), from a center of dilation, a Create a new image by scale factor, and an image, extending a line segment from Dilations may be performed on the center of dilation through polygons by drawing lines through Accurately find the length of each vertex of the original the center of dilation and each line segments and ratios of line figure by the scale factor to vertex of the polygon then segments, find each new vertex, marking off a line segment changed from the original by the Communicate with logical Present a convincing scale factor. reasoning a conjecture of argument that line segments generalization from created by the dilation are experimental results. parallel to their pre-images unless they pass through the A dilation uses a center and center of dilation, in which line segments through vertex case they remain on the same points to create an image line, which is similar to the original image but in a ratio specified Find the ratio of the length of by the scale factor, the line segment from the center of dilation to each The ratio of the line segment vertex in the new image and formed from the center of the corresponding segment in dilation to a vertex in the new the original image and image and the corresponding compare that ratio to the scale vertex in the original image is factor, equal to the scale factor. Conjecture a generalization of these results for all dilations.
Evidence of Student Attainment/Assessment Vocabulary Knowledge Skills Instructional Achievement Level Descriptors Students: Given a center of dilation, a scale factor, and a polygonal image, Create a new image by extending a line segment from the center of dilation through each vertex of the original figure by the scale factor to find each new vertex, Present a convincing argument that line segments created by the dilation are parallel to their pre-images unless they pass through the center of dilation, in which case they remain on the same line, Find the ratio of the length of the line segment from the center of dilation to each vertex in the new image and the corresponding segment in the original image and compare that ratio to the scale factor, Conjecture a generalization of these results for all dilations. Dilations Center Scale factor Students know: Methods for finding the length of line segments (both in a coordinate plane and through measurement), Dilations may be performed on polygons by drawing lines through the center of dilation and each vertex of the polygon then marking off a line segment changed from the original by the scale factor. Students understand/are able to: Accurately create a new image from a center of dilation, a scale factor, and an image, Accurately find the length of line segments and ratios of line segments, Communicate with logical reasoning a conjecture of generalization from experimental results. A dilation uses a center and line segments through vertex points to create an image which is similar to the original image but in a ratio specified by the scale factor, The ratio of the line segment formed from the center of dilation to a vertex in the new image and the corresponding vertex in the original image is equal to the scale factor. EEG-SRT.1-3. N/A (See EEG-CO.6-8.)
Geometry-Pacing-Guide-Version-3.docx