Skip to Main Content
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
you are here 4 239
quadrilaterals
What’s the total area of the lawn that Edward has asked you to
mow? How much should you charge? We’ve added on some extra
measurements to get you started.
18 meters
16 meters
20 meters
20 meters
12 meters
12 meters
18 meters
Let’s split the parallelogram
Think back to your work in previous chapters. When you needed
to find the total area of a shape you were unfamiliar with, you split
your shape up into other simpler shapes you were more familiar
with.
If you look carefully, you’ll see that the parallelogram is actually
made up of a central rectangle, with a right angle triangle on either
end. This means that to find the area of the parallelogram, we can
find the areas of these shapes, and then add them up together.
You can split a parallelogram into
a rectangle and two triangles.
240 Chapter 6
sharpen solution
What’s the total area of the lawn that Edward has asked you to
mow? How much should you charge?
18 meters
16 meters
20 meters
20 meters
12 meters
12 meters
18 meters
Area triangle 1 = 12 x 16 x 1/2
= 96 meters
2
Area of parallelogram = Area triangle 1 + Area rectangle + Area triangle 2
=96 + 288 + 96
= 480 meters
2
Charge = $0.10 x 480 = $48.00
Area triangle 2 = 12 x 16 x 1/2
= 96 meters
2
Area rectangle = 18 x 16
= 288 meters
2
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.
Start your free trial

You might also like

Make: Geometry

Make: Geometry

Joan Horvath, Rich Cameron
Classical Geometry: Euclidean, Transformational, Inversive, and Projective

Classical Geometry: Euclidean, Transformational, Inversive, and Projective

I. E. Leonard, J. E. Lewis, A. C. F. Liu, G. W. Tokarsky

Publisher Resources

ISBN: 9780596808365Errata Page