Unit 1A – Distance and Midpoint (Notes) Name: Objective(s): Key Concepts Date: Essential Question(s): Notes Distance Definition Distance on a Number Line What it looks like Formula Examples: Distance on a Coordinate Plane What it looks like Formula Examples: Find the distance between the following ordered pairs: 1. R (5, 1) and S (-3, -3) Page 1 Document1 Examples Continued: Find the distance between the following ordered pairs. 2. P (-4, 1) and Q (3, -1) 3. A (3, 4) and S (8, 0) 4. N (-2, -6) and M (-7, -5) Midpoint Definition Midpoint on a Number Line Formula Examples: 5. Find the coordinate of the midpoint of PQ 6. The coordinates on a number line of J and K are -6 and 8, respectively. Find the midpoint of JK . Page 2 Document1 Midpoint on a Coordinate Plane Formula Examples 7. Find the coordinates of the midpoint of GH for G (8, -6) and H (-14, 12). 8. Find the coordinates of M, the midpoint of PQ for (-1, 2) and Q (6, 1). P Sometimes you will be given the midpoint and you will need to find one of the endpoints. 9. Find the coordinates of X if Y (-2, 2) is the midpoint of XZ and Z has coordinates (2, 8). (Hint: Draw a picture if you need to.) 10. Find the coordinates of D if E (6, 4) is the midpoint of DF and F has coordinates (5, 3). Segment Bisector Definition Summary, Reflection, Analysis Page 3 Document1 Unit 1A – Distance and Midpoints Construction – Bisect a Segment Name Date You can construct a line that bisects a segment without measuring to find the midpoint of the given segment. Construction – Bisect a Segment 1. Draw a segment and name it ̅̅̅̅ 𝑋𝑌. Place the compass at point X. Adjust the compass 1 so that its width is greater than 2 𝑋𝑌. Draw arcs above and below ̅̅̅̅ 𝑋𝑌. 2. Using the same compass setting, place the compass at point Y and draw arcs above and below ̅̅̅̅ 𝑋𝑌 intersect the two arcs previously drawn. Label the points of the intersection of the arcs as P and Q. ̅̅̅̅. Label the point where it intersects 𝑋𝑌 ̅̅̅̅ as M. 3. Use a straightedge to draw 𝑃𝑄 Conclusion: 1. Point M is the _________________________ of ̅̅̅̅ 𝑋𝑌. 2. Segment PQ is a _________________________ of ̅̅̅̅ 𝑋𝑌. 3. Page 4 1 2 𝑋𝑌 = ___________________ = __________________ Document1 Unit 1A – Distance and Midpoints Assignment #1 Name Date Write the Distance Formula: Use the Distance Formula to find the distance between each pair of points. 1. A (0, 0) B (15, 20) 2. N (-12, 0) P (-8, 3) 3. C (11, -12) D (6, 2) 4. E (-2, 10) F (-4, 3) 5. G (-3, -4) H (5, 2) 6. Q (-3, 2) W (-2, -6) Page 5 Document1 Unit 1A – Distance and Midpoints Assignment #2 Name Date Write Midpoint Formula: Use the number line below to find the coordinate of the midpoint of each segment Page 6 Document1 Unit 1A – Distance and Midpoints Assignment #3 Name Page 7 Date Document1 For questions 4 and 5, construct two different size line segments and the bisect them using only a compass and a straightedge. 4. Page 8 5. Document1 Unit 1A – Distance and Midpoints Name: __________________ Geometry Activity Midpoint of a Segment Model ̅̅̅̅. Graph points A (5, 5) and B (-1, 5) on grind paper. Draw 𝑨𝑩 Hold the paper up to the light and fold the paper so that points A and B match exactly. Crease the paper slightly. Open the paper and put a point where the crease intersects ̅̅̅̅ 𝑨𝑩. Label this midpoint as C. Repeat the first three steps using endpoints X (-4, 3) and Y (2, 7). Label the midpoint Z. Answer the following questions: 1. What are the coordinates of point C? 2. What are the lengths of ̅̅̅̅ 𝑨𝑪 𝒂𝒏𝒅 ̅̅̅̅ 𝑪𝑩 ? 3. What are the coordinates of point Z? ̅̅̅̅ 𝒂𝒏𝒅 𝒁𝒀 ̅̅̅̅ ? 4. What are the lengths of 𝑿𝒁 5. What do you notice about the above segments? Page 9 Document1 Unit 1A – Distance and Midpoints Name: __________________ Page 10 Geometry Activity Document1 Page 11 Document1