This document contains notes from a math class on classifying triangles. It includes definitions and examples of different types of triangles classified by their angles (acute, obtuse, right) and sides (scalene, isosceles, equilateral). Students completed an activity where they classified triangles and practiced identifying different types of triangles. The document provides instruction on classifying triangles according to their properties and includes examples and practice problems for students to classify triangles and understand the different categories of triangles.

1. DAy 1 Triangles.notebook
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April 29, 2013
Jun 8­10:30 AM
Do Now
AIM: Classify Triangles
1.) In a bag there are 6 blue, 3 purple, and 1
pink marble, what is the probability of
randomly pulling a purple then a blue marble
without replacing the first?
2.) If you flip a coin and then roll a die,
what is the probability of getting a head
then an even number?
3.) Create a tree diagram that shows the
possible outcomes for flipping a coin, then
rolling a die, and then flipping another coin.
Feb 28­1:26 PM
Polygon
Jun 8­10:30 AM
Anticipatory Set:
Write the definition of each type of angle and then draw each type of angle.
Acute Angle Right Angle Obtuse Angle Straight Angle
Definition
Drawing
1.) Draw an additional line segment that will change the acute,
obtuse, and right angles into triangles.
2.) Why can the straight angle not be changed into a triangle if
you drew only one additional line segment?
Jun 8­10:30 AM
Classifying Triangles by Angle Measures
1.) Acute Triangle: A triangle where all angles are acute.
2.) Obtuse Triangle: A triangle that has one obtuse angle.
3.) Right Triangle: A triangle that has one right angle.
Classifying Triangles by Side Lengths
4.) Scalene Triangle: A triangle that has no congruent sides.
5.) Isosceles Triangle: A triangle that has at least two
congruent sides.
6.) Equilateral Triangle: A triangle that where all of the sides
are congruent.
Jun 8­10:30 AM
THINK-PAIR-SHARE
Classify each triangle according to its sides and angles.
a.) b.)
May 1­10:15 AM
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1 Indentify the triangle
below.
A Equilateral Triangle
B Isosceles Acute Triangle
C Isosceles Right Triangle
D Isosceles Obtuse Triangle
E Scalene Acute Triangle
F Scalene Right Triangle
G Scalene Obtuse Triangle

2. DAy 1 Triangles.notebook
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April 29, 2013
May 1­10:15 AM
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2
A
B
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G
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A
B
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5
A
B
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G
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6
A
B
C
D
E
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G
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7
A
B
C
D
E
F
G

3. DAy 1 Triangles.notebook
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April 29, 2013
May 1­10:15 AM
1 2
34
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A
B
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D
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G
May 1­10:15 AM
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Jun 8­10:30 AM
BEFORE YOU LEAVE: Trade-a-Triangle
1.) Create a triangle with your partner.
2.) Exchange the example with the other partnership in your
group and classify their triangle by the sides and angles.
Jun 6­8:45 AM
Homework: Cumulative Review Sheet #20 due tomorrow
Mr. Tjersland's Math 7
Feb 23­2:01 PM
AIM: Classify Triangles
10 Indentify the triangle
below.
A Equilateral Triangle
B Isosceles Acute Triangle
C Isosceles Right Triangle
D Isosceles Obtuse Triangle
E Scalene Acute Triangle
F Scalene Right Triangle
G Scalene Obtuse Triangle