November 2009
Beginner
368 pages
8h 55m
English
Content preview from Head First 2D Geometry
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
you are here 4 11
finding missing angles
Right angles often come in pairs
A right angle is a quarter turn, so two right angles add up to one
half turn—a 180º on your skateboard, assuming you land fakey
(facing the opposite way to when you started).
Slide rail
90º turn
90º turn
Skateboard
Although it doesn’t look like one, a
straight line is still an angle—exactly a
half turn, or two quarter turns.
Two right
angles sit
together on a
straight line.
The angle on a straight
line is a half-turn.
If this is a
right angle…
…this is also a
right angle.
Find the next mystery angle here…
180º
BULLET
PATH
MICKY
BENNY
FOOTPRINTS
18º
CRIME SCENE SKETCH
CASE GEO180
(ANGLES AS MEASURED
BUT DRAWING NOT TO
SCALE)
81º
86º
72º
?º
PLAN VIEW
12 Chapter 1
sharpen solution
BULLET
PATH
MICKY
BENNY
FOOTPRINTS
18º
CRIME SCENE SKETCH
CASE GEO180
(ANGLES AS MEASURED
BUT DRAWING NOT TO
SCALE)
81º
86º
72º
?º
PLAN VIEW
Find the next mystery angle here…
81º
?º
Often drawing a mini-sketch of
just the part you’re working out
makes things much clearer.
This is a right angle.
So the total angle made by these two
angles must also be a right angle.
? + 81º = 90º
? = 9º
you are here 4 13
finding missing angles
Great. Whatever. But what on earth
has working out the ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.