Current location - Training Enrollment Network - Mathematics courses - Beijing normal university printing plate eighth grade second volume mathematics textbook page 77 exercises the answer.
Beijing normal university printing plate eighth grade second volume mathematics textbook page 77 exercises the answer.
Answer: 1. Solution: (1) Point A is the center of rotation. Not good? CAE? DAF is the rotation angle;

(2)AB=AD=AF,AC=AE,BC=DE,CD=EF,? Bad =? CAE=? DAF? BAC=? DAE? CAD=EAF,? BCA=? DEA,? ACD=? AEF? ABC=? Ed. BCD=? DEF,? ADC=? AFE。

2. No, because the distance from the corresponding point to the rotation center should be equal before and after rotation, and OA? OC,OB? OD, so you can't rotate around the O point, so the AB line and the CD line coincide.

Bian Xiao suggested: