Congruent Segments, Angles, and Polygons Lesson

​Congruent Segments, Angles, and Polygons Lesson.

Today I am learning to determine
congruence of segments, angles, and
polygons.

I can
❏ Identify segments, angles, and

polygons.

❏ Identify which segments, angles, and

polygons are congruent.

​What is a Polygon?

• ​A polygon is any flat shape with three or more sides.

• Polygons are closed figures, which means that the lines are closed and not open.

Your turn!
Look at the
shapes on the
next set of
slides and see
if you can
guess
correctly!

Multiple Choice

Polygon or Not?

• Polygon

• Not

Multiple Choice

Polygon or Not?

• Polygon

• Not

Not a closed figure

Multiple Choice

Polygon or Not?

• Polygon

• Not

Curved, no
lines.

Multiple Choice

Polygon or Not?

• Polygon

• Not

Multiple Choice

Polygon or Not?

• Polygon

• Not

Multiple Choice

Polygon or Not?

• Polygon

• Not

Not a flat
shape. It is
a three
dimensional
shape!

Multiple Choice

Polygon or Not?

• Polygon

• Not

Congruent vs Similar

What is the difference?

Similar vs. Congruent

Notice that the similar shapes are the SAME SHAPE but DIFFERENT
SIZE..

Notice the congruent shapes are SAME SIZE and SAME SHAPE.

Multiple Select

Which of these pairs of figures are similar?

Answer

Multiple Select

Which of these pairs of figures are congruent?

Answer

Multiple Choice

Congruent, Similar, or Neither?

• Congruent - same size and same shape.

• Similar - same shape, but different sizes.

• Neither - neither same size nor same shape.

Multiple Choice

Congruent, Similar, or Neither?

• Congruent - same size and same shape.

• Similar - same shape, but different sizes.

• Neither - neither same size nor same shape.

Multiple Choice

Congruent, Similar, or Neither?

• Congruent - same size and same shape.

• Similar - same shape, but different sizes.

• Neither - neither the same size nor the same shape.

Multiple Choice

Congruent figures have...

• the same number of sides

• the same shape, but different sizes

• the same shape and size

• are different shapes

Multiple Select

Which of the following are true when comparing and contrasting congruent and similar shapes? (Pick all that are true.)

• Both need to be exactly the same shape.

• Similar shapes need to be the same size.

• There are no differences between the two.

• Only congruent shapes need to be the same size.

​What is symmetry?

​When something is symmetrical, you can cut it in half and it is the same on both sides.

The line used to cut it in half is called the line of symmetry.

Line of Symmetry

• Line of Symmetry divides a figure into two congruent parts, each of which is the mirror image of the other.

• The number of lines of symmetry of a regular polygon is equal to the number of sides of the polygon.

• Lines of symmetry are not limited to horizontal and vertical lines.

Multiple Choice

Symmetrical?

• Is symmetrical

• not symmetrical

Multiple Choice

• is symmetrical

• not symmetrical

Multiple Choice

Symmetrical?

• Is symmetrical

• not symmetrical

Multiple Choice

Symmetrical?

• Is symmetrical

• not symmetrical

Multiple Choice

How many lines of symmetry does the picture have? 

• 0 lines of symmetry
• 1 line of symmetry
• 2 lines of symmetry
• 4 lines of symmetry

# of sides of a regular polygon
=
# of lines of symmetry

Multiple Choice

How many lines of symmetry for this regular polygon?

• 3

• 6

• 1

• 9

Multiple Choice

How many lines of symmetry for this regular polygon?

• 4

• 2

• 8

• 16

Multiple Choice

How many lines of symmetry for this 9- sided regular polygon?

• 9

• 18

• 27

• 3

Multiple Choice

How many lines of symmetry for this 7 - sided regular polygon?

• 14

• 7

• 21

• 1

Symbols used to show congruence

Multiple Choice

Are these two segments congruent?

• Yes! They are the same length.

• No! They are different lengths.

Multiple Choice

If AB is congruent to CD, then what is the measure of CD?

• 5 cm

• 8 cm

• 13 cm

• There is no way to know!

Multiple Choice

Are the following angles congruent?

• Yes!

• No!

• There is no way to know!

Multiple Choice

$$\overline{AB}\ \cong\ ?$$

• $$\overline{MN}$$

• $$\overline{NO}$$

• $$\overline{OP}$$

• $$\overline{PM}$$

Multiple Choice

$$\overline{PQ}\ \cong\ ?$$

• $$\overline{FE}$$

• $$\overline{ED}$$

• $$\overline{DG}$$

• $$\overline{GF}$$

Multiple Choice

$$\overline{GP}\ \cong\ ?$$

• $$\overline{KR}$$

• $$\overline{RF}$$

• $$\overline{FK}$$

Multiple Choice

$$\overline{CD}\ \cong\ ?$$

• $$\overline{RT}$$

• $$\overline{TP}$$

• $$\overline{PS}$$

• $$\overline{SQ}$$

• $$\overline{QR}$$

Multiple Choice

Quadrilateral EFGH is congruent to Quadrilateral WXYZ.

Which line segment is congruent to $$\overline{EF}$$ ?

• $$\overline{WX}$$

• $$\overline{XY}$$

• $$\overline{YZ}$$

• $$\overline{ZW}$$

Multiple Choice

Quadrilateral STUV is congruent to Quadrilateral EFGH.

Which line segment is congruent to $$\overline{UV}$$ ?

• $$\overline{ST}$$

• $$\overline{TU}$$

• $$\overline{EF}$$

• $$\overline{GH}$$