This web page lists errors that have been discovered in the first edition of the Instructor's Resource Manual to Accompany Geometry with Geometry Explorer, by Mike Hvidsten, published by McGraw-Hill, January 2005.  Please note that any changes involving mathematical notation are expressed in TeX form.
If you discover errors other than those listed, please email them to hvidsten(at)gustavus.edu

Page(s)	Line(s)	Description	Date	Discoverer
13	Ex 2.1.5	We don't need to use Theorem 2.9 to claim that the sum of the angles is two right angles. Just use supplementary angles and the fact that the angle at B is congruent to the angle at A.	2-20-2009	Amy Wehe
25	3,4	Replace "AQO" with "AQP" on line 3. Replace "BQO" with "BQP" on line 4.	9-20-2005	Mike Hvidsten
61	13 (-1)	Replace "The symmetry group is p4." with "The symmetry group is p4g. There is a line of reflection that does not pass through the center of rotation of the figure. This line of reflection can be any of 4 lines that make up the "square" in Fig. 6.6."	11-3-2005	Geometry class at Gustavus - fall 2005
67	13	Replace "as shown" with "as shown with DC = GH and the angles at D and C congruent to the angles at H and G."	12-6-2005	Mike Hvidsten
67	15	Replace "HI > AD and GJ > BC" with "HI = AD and GJ = BC"	12-6-2005	Mike Hvidsten