Download 3.6 Congruent Triangles - Fort Thomas Independent Schools

3.6 Congruent
Triangles
I can describe different types of
triangles.
I can identify different types of
triangles.
I can explain and use methods to
copy triangles.
Marks
Marks are used to show that sides
of a figure are the same length .
The number of marks has no
meaning – it does not
indicate that any sides are
longer than others.
Journal Page 75
 Use
this page to determine the
characteristics of each type of triangle



Equilateral
Isosceles
Scalene
Complete with a partner.
Definitions and Examples
An equilateral triangle has sides that are all the same
length.
An isosceles triangle has at least two sides that are the
same length.
(Can an equilateral triangle be
considered an isosceles triangle
also?)
A scalene triangle does not have any sides that are the
same length.
A right triangle has a right angle at one of its
vertices.
Which one is a
right triangle?
What do we call figures that
are exact (same size, same
shape) copies?
Congruent figures
NOTE: Congruent figures are exact copies;
they are the same size and the same
shape.
Angles and sides
Making copies using available
tools
 Protractor
 Compass
 Ruler
 Straightedge
Review SRB 165 and 166
Naming congruent figures
Math Journal page 76
Read all directions then put both hands on your head.
You will have to explain, step by step, how you created
PAL, so write down each thing you do, before you
move on to the next step.
Remember that points of PAL must correlate to
respective points of BIG.
Before you tape PAL, lay the cut-out over BIG to
confirm that they are congruent.
Copying a Triangle without a
Protractor
 Review
SRB 166 and explain this method
to a partner.
Choose a partner and discuss how you would do #1 on
journal page 77
Try #1 on journal page 77 with your partner (5 minutes)
Let’s do it as a class
Journal page 77 #2
 Complete
partner.
this problem with a different
Journal page 78
Read the directions.
You will only draw one triangle.
Trade with a different partner.
Math Boxes page 79
 Raise
your hand to be checked.
 Homework: Study Link 3.6
Games
Angle Tangle – SRB 296
Sides and Angles: Triangles
MM 502