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Class Opener ‐ Use the figure at the right to answer the true/false questions below.

1. A, G, and C are collinear.

2. A, G, and D are coplanar.

3. D and E lie on a ray.

4. G lies on the intersection of two lines.

5. C lies on the intersection of a segment and a line.

6. Angle FGC is a right angle.

7. Angle ECG is obtuse.

8. G, D, and F lie on the same plane.

9. Ray AG and Ray GC are opposite rays.

A

G

C

D

E F

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Homework Questions:

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Section 1.2: Measuring (and Constructing) Segments

Absolute Value Review: What does it actually mean?

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Finding lengths of segments.What's the difference between IF and IF ???

F I S H

‐3 2.5 5 8

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What about when things are the same???

2 identical segments 2 equal angles 2 twin triangles

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What is the relationship between CA, CT, and AT???

Where is A at?

C A T

g

C A T

g

Would you describe A in the same way in the picture below?

C T

g

A

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Try this...

1. B is between A and C. AC = 14, and BC = 11.4. Find AB.

2. S is between R and T. RS = 2x + 7, RT = 4x, and ST = 28. Find RT.

3. R is between Q and P. QR = x2 ‐ x, RP = ‐2x, and QP = 54. Find RP.

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What's interesting about the picture below???

C A T

g

Another name for what is happening...

These can be created by 4 different things. What do you think they are???

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Try This...Make sure you're thinking!

1. B is the midpoint of AC. AB = 5x, and BC = 3x + 4. Find AB, BC, and AC.

2. A is the midpoint of RT. RT = 4x ‐ 2, and RA = 2x + 1. Find AT.

3. O is the midpoint of DG. DG = 20, and DO = 2x + 5. Find GO. Find x.

4. S is the midpoint of RT. RS = ‐2x, and ST = ‐3x ‐ 2. Find RS, ST, and RT.

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Try these on your own!!!

1. U is the midpoint of XY. Find XY if XU = x2 + 4x ‐ 3 and UY = x2 + 2x + 5.

2. U is the midpoint of XY. Find XY if XY = 3x2 + 5x and UY = x2 ‐ 2x ‐ 7.

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