1.2 Measuring and Constructing Segments.notebook
August 17, 2016
In your foldable (segments section)
When segments have the same measure (length), they are
congruent.
PQ = RS, so you can write PQ ≅ RS.
The midpoint of a segment bisects the segment
M
A
B
If M is the midpoint of AB, then AM = MB.
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1.2 Measuring and Constructing Segments.notebook
August 17, 2016
What we will learn today:
~ To use length and midpoint of a
segment, and
~ To construct midpoints and congruent
segments.
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1.2 Measuring and Constructing Segments.notebook
August 17, 2016
In order for you to say that a point B is between two points A
and C, all three points must lie on the same line, and
AB + BC = AC.
In your foldable (segments section)
Example 2: Using the Segment Addition Postulate
A. G is between F and H, FG = 6, and FH = 11. Find GH.
B. M is between N and O. Find NO.
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1.2 Measuring and Constructing Segments.notebook
August 17, 2016
In your foldable (segments section)
When segments have the same measure (length), they are
congruent.
PQ = RS, so you can write PQ ≅ RS.
4
1.2 Measuring and Constructing Segments.notebook
August 17, 2016
The midpoint of a segment is the point that divides
the segment into two congruent segments.
A segment (or angle) is bisected when it is divided
into two congruent segments (or angles).
So, the midpoint of a segment bisects the segment.
M
A
B
If M is the midpoint of AB, then AM = MB.
In your foldable (segments section)
Example 4: Using midpoint to find length
A. D is the midpoint of EF, ED = 4x + 6, and DF = 7x – 9.
Find ED, DF, and EF.
B. S is the midpoint of RT, RS = –2x, and ST = –3x – 2.
Find RS, ST, and RT.
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1.2 Measuring and Constructing Segments.notebook
August 17, 2016
Example 5: Applications
A. The map shows the route for a race. You are at X,
6000 ft from the first checkpoint C. The second
checkpoint D is located at the midpoint between C and
the end of the race Y. The total race is 3 miles. How far
apart are the 2 checkpoints? (Assume the race route
travels in a straight line)
B. You are 1182.5 m from the first-aid station. What is the
distance to a drink station located at the midpoint
between your current location and the first-aid station?
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1.2 Measuring and Constructing Segments.notebook
August 17, 2016
Geometric Constructions
Construction in Geometry means to draw
shapes, angles or lines accurately.
These constructions use only compass,
straightedge, and a pencil.
This is the pure form of geometric construction no numbers involved!
Gather your group ~
Find 2 or 3 other students who have the same birth
month as you (to create groups of 3 or 4).
Each person in the group needs a compass, a
straightedge, and a pencil.
I will be handing out the Constructions sheet as you
form your groups and collect your supplies.
YOU HAVE 2 MINUTES STARTING NOW!!!
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