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Head First 2D Geometry
book

Head First 2D Geometry

by Stray (Lindsey Fallow), Dawn Griffiths
November 2009
Beginner content levelBeginner
368 pages
8h 55m
English
O'Reilly Media, Inc.
Content preview from Head First 2D Geometry
46 Chapter 1
your geometry toolbox
A square mark indicates a
RIGHT ANGLE (90º).
Your Geometry Toolbox
You’ve got Chapter 1 under your
belt, and now you’ve added
techniques for finding missing
angles to your toolbox. For a complete
list of tool tips in the book, visit
www.headfirstlabs.com/geometry.
Angles can be made
up of other, smaller
angles.
Angles in a four-sided
shape add up to 360º.
Angles in a triangle
add up to 180º.
Angles on a straight
line add up to 180º.
CHAPTER 1
you are here 4 47
finding missing angles
If two angles add up
to 180º, they are
SUPPLEMENTARY.
If two angles add
up to 90º, they are
COMPLEMENTARY.
Parallel lines make repeat
sets of vertical angles.
F, Z, and N patterns
around parallel lines save
you a ton of math.
Vertical angles are
equal (and opposite
each other).
48 Chapter 1
who does what solution
Angles in a triangle add
up to 180º
Match each technique for finding missing angles to a sketch. You can use
each technique just once, but some sketches will need more than one to
find the missing angle.
Vertical angles are equal
Parallel lines cross other
lines at the same angles
Angles on a straight line add
up to 180º
Angles in a right angle add
up to 90º
Angles in a four-sided ...
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Publisher Resources

ISBN: 9780596808365Errata Page