Unit 1, Lesson 3
Making Scaled Copies
Grade 7
Sign in to view assessments and invite other educators
Sign in using your existing Kendall Hunt account. If you don’t have one, create an educator account.
Figure A is a quadrilateral with side lengths 2, 3, 3, and diagonal side up 3 over 1 units. Figure B is line that goes right 1 unit, up 3 units, diagonal down 4 and right 2 units, up 3 units, and right 2 units. Figure C is a 6 unit by 3 unit rectangle with a 2 unit by 4 unit rectangle appended to the left top 2 squares and a 1 unit by 2 unit rectangle appended to the top right square. Figure D is a line forming the number 2 that is 10 units tall and 6 units wide.
Diego and Jada want to scale this polygon so the side that corresponds to 15 units in the original is 5 units in the scaled copy.
Diego and Jada each use a different operation to find the new side lengths. Here are their finished drawings.
Diego's drawing has 6 side lengths of 26, 8, 5, 2, 11, and 20, but the sides do not connect to form a closed figure.
Jada's drawing is a rectangle of height 10 and length 12 with a rectangle of height 4, length 5 removed from the bottom right corner.
Andre wants to make a scaled copy of Jada's drawing so that the side that corresponds to 4 units in Jada’s polygon is 8 units in his scaled copy.
Andre says “I wonder if I should add 4 units to the lengths of all of the segments?” What would you say in response to Andre? Explain or show your reasoning.
Create the scaled copy that Andre wants. If you get stuck, consider using the edge of an index card or paper to measure the lengths needed to draw the copy.
Jada's drawing is a rectangle of height 10 and length 12 with a rectangle of height 4, length 5 removed from the bottom right corner.
Creating a scaled copy involves multiplying the lengths in the original figure by a scale factor.
For example, to make a scaled copy of triangle