Mr. Williams
GESD
jwilliams@gesd40.org
9.4 Classifying Triangles
Objective: Classify triangles
by their angles and sides.
Image: '< < <'
www.flickr.com/photos/57301170@N00/1938697463
1

Acute Triangle
­ Has three acute
angles.
Image: 'Quack'
www.flickr.com/photos/44124404848@N01/45433962
2

Obtuse Triangle
­ A triangle with
one obtuse angle.
http://www.flickr.com/photos/cvangundy4/480668676/
Obtuse Triangle
3

Right Triangle
­ A triangle
with one right
angle.
http://www.flickr.com/photos/cvangundy4/480664752/
4

Your Turn:
In your group classify the triangles
by their angles.
pg. 436 problems 1 ­ 3
Image: 'Ławki w Olympiastadion w Monachium'
www.flickr.com/photos/92011564@N00/267683634
5

Equilatral Triangle
A triangle that has
all three sides the
same length.
Image: 'Splash3'
www.flickr.com/photos/73491156@N00/477332444
6

Isosceles Triangle
A triangle that has
two sides the same
length.
7

Scalene Triangle
A triangle that has
three sides of
different lengths.
8

The angles on a
triangle always add
up to 180 degrees!
Image: 'ATT….EN……TION…..'
www.flickr.com/photos/7166367@N05/1534572737
9

Your Turn:
With your group, answer
questions 1 ­ 10 on p. 438.
10