Pearson Geometry Common Core, 2011
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Pearson Geometry Common Core, 2011 View details
3. Measuring Segments
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Exercise 42 Page 25

A midpoint is in the middle of a segment and splits the length in half.

GH=30

Practice makes perfect
Let's look at each midpoint and create a diagram to visualize the described situation. C is the midpoint of AB Since C is the midpoint, it is halfway in between A and B.

Using the same reasoning, we will place all of the listed midpoints in the middle of the given segments.

Given Description Number line
D is the midpoint of AC
E is the midpoint of AD
F is the midpoint of ED
G is the midpoint of EF
H is the midpoint of DB

We are then told that the length DC is equal to 16. We can label this distance on our diagram and use our knowledge of the midpoints and the Segment Addition Postulate to find the length of GH.

Reasoning Number line
DC=16
D is the midpoint of AC, so AD=DC.
AC=AD+DC, so AC=32. C is the midpoint of AB, so CB=32.
DB=DC+CB, so DB=48. H is the midpoint of DH, so DH= 24.
E is the midpoint of AD, so AE=ED=8.
F is the midpoint of ED, so FD=EF= 4. G is the midpoint of EF, so EG= GF= 2.

Finally, to find GH, we can use the Segment Addition Postulate to add GF, FD, and DH. GF+ FD+ DH= GH ⇒ 2+ 4+ 24= 30