G-CO.D.12
Make formal geometric constructions with a variety of tools and methods (compass and straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.). Copying a segment; copying an angle; bisecting a segment; bisecting an angle; constructing perpendicular lines, including the perpendicular bisector of a line segment; and constructing a line parallel to a given line through a point not on the line.
Example Problems
Point A is at and point C is at .
Find the coordinates of point B on such that .
Find the coordinates of point B on such that .
Point A is at and point C is at .
Find the coordinates of point B on such that .
Find the coordinates of point B on such that .
Point A is at and point C is at .
Find the coordinates of point B on such that .
Find the coordinates of point B on such that .
Khan Academy ResourcesJustify constructionsGeometric constructions: perpendicular bisectorGeometric constructions: angle bisectorGeometric constructions: perpendicular line through a point on the lineGeometric constructions: parallel lineGeometric constructions: perpendicular line through a point not on the lineGeometric constructions: congruent angles

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