- Page 14, line 16. Change "will used" to "will be used".
- Page 17, line 2. Delete the second "all".
- Page 65, line 7. Change "segments \(\overline{BC}\)" to "segment \(\overline{BC}\)".
- Page 76, line 12. Change "Corollary 5.7.3" to "Corollary 3.2.19". [Corrected in the third printing.]
- Page 76, line 18. Change "Theorem 5.7.10" to "Theorem 3.3.10". [Corrected in the third printing.]
- Page 76, line 29. Change "\(\mu(\angle HCB)=\mu(\angle HCB)\)" to "\(\mu(\angle HCB)=\mu(\angle HGB)\)"
- Pages 96 and 97, second half of the proof of Theorem 4.7.7. The proof assumes \(S\) and \(T\) are on the same side of \(\overleftrightarrow{PQ}\).
If not, use Theorem 4.2.6 to construct a triangle congruent to \(\triangle PQT\) on the other side of \(\overleftrightarrow{PQ}\) and use it instead.
- Page 114, line 1. Change "the the" to "the".
- Page 135, line 23. Change "\(\angle BAD \cong \angle CDA\)" to "\(\angle BCD \cong \angle CDA\)".
- Page 141, line 9. Change "\(K\) in a half open interval" to "\(K\) is a half open interval".
- Page 145, line 24. Change "point \(T\) on \(\overrightarrow{AB}\)" to "point \(T\) on \(\overrightarrow{AE}\)".
- Page 145, line 29. Change "the ray \(\overrightarrow{AT}\)" to "the ray \(\overrightarrow{PT}\)"
- Page 152, Definition 6.6.1. Change "if they contain asymptotically parallel rays" to "if they contain limiting parallel rays".
- Page 164, line 9. Change "equilateral decreases" to "equilateral triangle decreases".
- Page 170, two lines after Figure 7.6. Change "either use" to "use either".
- Page 173, Axiom 7.2.1. Change "\(\alpha(\square ABCD) = AB \cdot CD\)" to "\(\alpha(\square ABCD) = AB \cdot BC\)" [Corrected in the third printing.]
- Page 179, Exercise 1. Change "\(\alpha(\triangle ABC)=(1/2)\ AB \cdot BC\)" to "\(\alpha(\triangle ABC)=(1/2)\ AC \cdot BC\)" [Corrected in the third printing.]
- Page 191, line 1. Change "\(MP>(1/2)\ DF\)" to "\(AP>(1/2)\ DF\)"
- Page 361, line 2. Change "Hlibert's" to "Hilbert's".
- Page 361, line 6. Change "HIlbert" to "Hilbert".
- Page 375, hint for Exercise 7.2.1. Change "Theorem 7.1.7" to "Theorem 7.1.8".
- Page 376, hint for Exercise 8.2.1. Change "Exercise 7" to "Exercise 5.6.7". [Corrected in the third printing.]
- Page 376, hint for Exercise 8.3.5. Change "Exercise 3" to "Exercise 4.6.3". [Corrected in the third printing.]
- Page 377. Change "10.1.12" to "10.1.14".