Triangles
Middle School Math
Aligned to Common Core State Standards
Teacher Notes
Insight 360™ is eInstruction’s classroom instruction system that allows you to
interact with your students as they learn, quickly gaining insight into student
understanding during class so you can adjust instruction in real-time during a
single class session.
Use this content, designed specifically for use with Insight 360™, to interact
with your class. This content includes brief instructional material and two
types of activities:
Constructed Response Activity for students to complete as an individual
or a group assignment. Send each Constructed Response Activity to the
Insight 360 iPad Student App.
Assessment Item with CueTag™ for students to respond to via student
response devices. Receive instant real-time feedback and longitudinal
reports.
Triangles
Triangles are three-sided closed figures.
What do you know about triangles?
Write what you know about triangles on the lines below.
Triangles
What do you know about triangles?
Write what you know about triangles on the lines below.
Answers may vary
3 sides
Can have 3 equal sides
Can have 2 equal sides
Length of sides can differ
3 angles
Angle measure can differ
Triangles
Named by the lengths of
sides or by the measure
of the angles
Can have three different sides
and angles
How can we categorize triangles?
Fill in the blanks.
Triangles
Length of Sides
Types of Angles
How can we categorize triangles?
Fill in the blanks.
Answers may vary.
Triangles
Length of Sides
Types of Angles
Scalene – No sides equal
Acute – All angles < 90
Isosceles – 2 or more sides equal
Obtuse – One angle > 90
Equilateral – 3 sides equal
Right – One angle = 90
Right Angles
The sides of a right angle are perpendicular lines. Right angles are denoted
using a square located at the vertex of the angle.
A
B
Angle ABC is a right angle.
C
Right Angle Activity
Draw pictures of right angles found in your classroom.
Right Angle Activity
Draw pictures of right angles found in your classroom.
Answers may vary and may include the corner of a shelf or picture frame.
Right Triangle Activity
Right triangles have one right angle. Circle all the right triangles.
Right Triangle Activity
Right triangles have one right angle. Circle all the right triangles.
Identify Triangles
Describe each triangle by sides and angle measures.
Identify Triangles
Describe each triangle by sides and angle measures.
scalene right triangle
obtuse isosceles triangle
equilateral triangle
scalene obtuse triangle
isosceles right triangle
scalene right triangle
scalene right triangle
acute isosceles triangle
A right scalene triangle has
a.
one angle more than 90 and two sides the same length.
b.
one angle equal to 90 and no sides the same length.
c.
one angle equal to 90 and two sides the same length.
d.
one angle more than 90 and no sides the same length.
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