Early printings of the course guide did not include sample responses for each modeling prompt. To access these, visit the modeling prompt pages online.

In the Course Guide, under Scope and Sequence, the Pacing Guide for Geometry Unit 7 was edited to indicate that none of the lessons in that unit are optional.

Unit 1 Narrative. Insert as the second-to-last paragraph: "A blank reference chart is provided for students, and a completed reference chart for teachers. The purpose of the reference chart is to be a resource for students to reference as they make formal arguments. Students will continue adding to it throughout the course. Refer to About These Materials in the Geometry course for more information."

Unit 1, Lesson 11, Activity 2. Data Card 1 is updated to remove the bullet about the image of points \(F\) and \(G\).

Unit 1, Lesson 12. One of the learning targets said, "I can describe a reflection by stating the directed line segment." Changed reflection to translation.

Unit 1, Lesson 12, Lesson Summary. Removed stray "1." and "8" from the summary.

Unit 1, Lesson 13. The second bullet should say "clockwise" instead of counterclockwise.

Unit 1, Lesson 14, Info Gap activity. An image of labeled points was missing from the task statement. This image is now in place in the online materials.

Unit 2 Narrative. Add these 2 sentences to the end of the note on materials: “Students will continue to use and add to their reference charts. The completed reference chart for this unit is provided for teacher reference.”

Unit 2, Lesson 1, Practice Problem 6. Updated solution. Part a has the letters in the correct order, and part b uses to a rotation.

Unit 2, Lesson 2, Practice Problem 7. In the solution for the second question, EFAGLK is taken to hexagon ABCIHG.

Unit 2, Lesson 3, Practice Problem 5. The solution to part a now reads, "Angle A is not congruent to angle S as Tyler's statement indicates."

Unit 2, Lesson 3, Practice Problem 6. Choice E is now, "Angle CBA is congruent to angle FED."

Unit 2, Lesson 4, Practice Problem 6. Question 2 refers to quadrilaterals, not pentagons.

Unit 2, Lesson 7, Practice Problem 4. The image is updated to show that AD is congruent to AC.

Unit 2, Lesson 11, Activity 3. In the Are You Ready for More section, students should construct BD to be the same length as BC.

Unit 2, Lesson 11, Practice Problem 3. Choice A now refers to angles CBE and DAE.

Unit 2, Lesson 13, Practice Problem 7. Choices are updated to less ambiguous phrasing.

Unit 2, Lesson 15, Practice Problem 2. The last line of the proof should say line EG is the line of symmetry.

Unit 3, Lesson 3, Activity 3. The image of showed quadrilateral \(ABDC\). The labels for \(C\) and \(D\) are now changed so that it is \(ABCD\) as intended. The solution image is also updated to reflect the change.

Unit 3, Lesson 8, Practice Problem 7. Updated instructions to, "Select all true statements given that angle \(AED\) is congruent to angle \(ABC\)."

Unit 3, Lesson 9, Lesson Synthesis. Corrected the first bullet to say that 2 congruent angles in a triangle show that the two triangles are similar.

Unit 3, Lesson 13, Practice Problem 7. Updated choice A to read, "Triangle BDE is congruent to triangle EFC," choice B to read, "Triangle BDE is congruent to triangle DAF," and the solutions to include both of those options.

Unit 3, Lesson 16, Activity 2. In the digital version of the activity, the solution image and value for the third question are updated to match the digital applet.

Unit 4, Lesson 1, Practice Problem 5. Changed the question to, "If segment \(BD\) has length \(\frac{4}{3}\), calculate the length of side \(DE\)."

Unit 4, Lesson 4, Activity 2. The applet linked in the digital launch is updated so that column G now computes opp/adj.

Unit 4, Lesson 8, Practice Problem 8. The question is updated to include that the handball court is 20 feet wide and 34 feet deep. The solution is updated to 7.36 feet away from point C.

Unit 5, Lesson 11, Activity 2. The solution for the volume of solid F is corrected to 30.0 cubic centimeters.

Unit 5, Lesson 13, Practice Problem 7. The solution to the first question is 1,440 cubic centimeters.

Unit 5, Lesson 17, Activity 2. The solution to the Are You Ready for More? question used the wrong units. The solution has been updated.

Unit 5, Lesson 17, Practice Problem 5. Updated the suggested solution cylinder height to 34 units and the suggested rectangular prism to dimensions 2 by 3.2 by 8.

Unit 5, Lesson 18, Activity 3. The image was incorrectly labeled to use the value 14.04. It has been corrected to 14.14.

Unit 5, Lesson 18, Practice Problem 2. The solution for the second question uses 170 square inches so that the ratio is \(\frac{17}{15}\).

Unit 5, Lesson 18, Practice Problem 3. Updated statement values to better values. Radius is 4 units. Volume is \(16\pi\) square units.

Unit 5, End of Unit Assessment, Problem 3. The cone with radius 6 and height 6 is labeled shape C.

Unit 6, Lesson 1, Cool Down. The labels for points B and C are switched to match the description of the problem.

Unit 6, Lesson 2, Activity 3. The sample solution now correctly refers to figures Q, R, and S respectively.

Unit 6, Lesson 3, Activity 2. Graph B is updated so that the vertices of \(F'\) are at \((2,1), (4,1), (4,3)\). Updated rule 3 to be \((\text-2x,y)\)

Unit 6, Lesson 5, Practice Problem 2. The equation of the circle is \( x^2 - 8x + 16 + y^2 + 10y + 25 = 81\) .

Unit 6, Lesson 8, Activity 3. In the blackline master, equation C should be \((x+3)^2 + (y-2)^2 = (y-1)^2\).

Unit 6, Lesson 9, Lesson Synthesis. Each of the bulleted equations has been updated to use 4 instead of 3 to match the graph.

Unit 6, Lesson 11, Activity 3. Corrected solution for part 4 for Are You Ready for More is \((\frac{a+c}{2}, \frac{b}{2})\).

Unit 6, Lesson 15, Activity 3. Corrected solution for part 2 for Are You Ready for More uses the slopes \(\frac{d}{c}\) and \(\frac{f-b}{e-a}\).

Unit 6, Lesson 16, Lesson Summary. Point \((0,w)\) is corrected to \((w,0)\) and matches what is in activity 3

Unit 7, Family Support Materials. The solution for the first question now has a correct reasoning and solution involving \(\pi\).

Unit 7, Lesson 1, Practice Problem 7. Switched points C and D in the image.

Unit 7, Lesson 5, Activity 3. The solution to the second question had the triangles in the wrong order.

Unit 8, Lesson 2, Practice Problem 3. Updated the solution to refer to the letter L instead of P.

Unit 8, Lesson 3, Activity 3. The statement now includes the word "exactly" and the last part should refer to exactly 4 items. In the extension solution, the first outcome in the set should use C3. The solution to the question about exactly 3 items should be \(\frac{4}{24}\)

Unit 8, Lesson 4, Activity 3. The fraction in the solution should be \(\frac{447}{2,234}\). The decimal value was correct. The total number of commuters in Austin is 627 and overall is 1,104.

Unit 8, Lesson 4, Cool-down. The total for the first column should be 19,195.

Unit 8, Lesson Synthesis. Updated solution to second bulleted question to \(\frac{7}{20}\).

Unit 8, Lesson 4, Practice Problem 7. The solution to the second part is 6/16.

Unit 8, Lesson 6, Lesson Summary. The formula now correctly refers to "medium" and "blue" as the correct characteristics.

Unit 8, Lesson 6, Lesson 2. A question referred to Alaska as being one of 12 states in the top left cell of the table. There are only 11 states in the top left cell of the table.

Unit 8, Lesson 6, Practice Problem 6. The solution to part b is 0.67.

Unit 8, Lesson 7. Corrected the learning target to, "I can explain the difference between dependent and independent events."

Unit 8, Lesson 8. Corrected the learning target to, "I can use the multiplication rule \(P(\text{A and B}) = P(\text{A | B}) \boldcdot P(\text{B})\) to find conditional probabilities."

Unit 8, Lesson 9, Activity 2. The Are You Ready for More? did not make sense. A new one is available.

Unit 8, Lesson 9, Activity 3. The calculations in the activity syntheses are corrected. The first bulleted question should use \(\frac{0.015}{0.1}=0.15\) and the third bulleted question should use \(\frac{0.006}{0.15}=0.04\).

Unit 8, Lesson 9, Lesson Synthesis. The last bullet of the lesson synthesis now has a corrected suggested solution \(P(\text{orange} | \text{female}) = \frac{12}{30}\).

Unit 8, Lesson 9, Practice Problem 2. The table is updated to include 50 results and the solutions are updated to match the new values.

Unit 8, Lesson 10, Warm-up. Corrected possible responses. For Set 2, use \(P(B \vert A) = 1\) and for Set 4, \(P(A \text{ and } B) = 0\).

Unit 8, Lesson 10, Practice Problem 2. The third part has been rewritten to be more clear about the events.

Unit 8, Lesson 11. Paper bags are added to the required materials for playing the game.

Unit 8, End of Unit Assessment. Option F had the incorrect inequality. It is corrected to \(P(\text{bus | middle school}) > P(\text{bus | high school})\)