Grades 7-8 Video Solutions 2025-2025_7-8

Video Transcription

Video Summary

In the given geometry problem, we need to find the length of BC in rectangle ABCD, with points E and F on DC such that angles EBA and DFA each measure 45 degrees, and AB + EF equals 20 cm. By analyzing the rectangle and using the associative property of addition, we express the sum AB + EF in terms of other segments. Triangles ADF and EFC are isosceles, leading us to equate AD with FD and BC with EC. Consequently, BC + BC equals 20 cm. Thus, BC is determined to be 10 cm, corresponding to option D.

Keywords

rectangle

geometry

isosceles

angles

length