Answer the questions

Illustrative Mathematics Lesson 15 Practice Problems 1. Select all quadrilaterals that have 180 degree rotational symmetry. A. trapezoid B. isosceles trapezoid C. parallelogram D. rhombus E. rectangle F. square (From Unit 2, Lesson 14.) 2. Lin wrote a proof to show that diagonal EG is a line of symmetry for rhombus EFGH. Fill in the blanks to complete her proof. Because EFGH is a rhombus, the distance from E to is the same as the distance from E to 2 Since E is the same distance from 3 as it is from 4 _, it must lie on the perpendicular bisector of segment 5 By the same reasoning, G must lie on the perpendicular bisector of 6 . Therefore, line 7 is the perpendicular bisector of segment FH. So reflecting rhombus EFGH across line 8 will take E to 9 and G to 10 (because E and G are on the line of reflection) and F to 11 and H to 12 (since FH is perpendicular to the line of reflection, and F and H are the same distance from the line of reflection, on opposite sides). Since the image of rhombus EFGH reflected across EG is rhombus EHGF (the same rhombus!), line EG must be a line of symmetry for rhombus EFGH. (From Unit 2, Lesson 14.) Geometry Unit 2 CC BY 2019 by Illustrative Mathematics@ Lesson 15