MATHS TOPIC: Congruence -Compare & Contrast Geometric Shapes

FOCUS QUESTION:     What are the properties of the various plane figures around us?

SPECIFIC OBJECTIVE: 

1.     Describe congruence in plane and solid shapes.
2. Distinguish between similar and congruent figures (triangles and quadrilaterals)

CONTENT
In summary, congruent shapes are figures with the same size and shape. The lengths of the sides and the measures of the angles are identical. They're exact copies, even if one is oriented differently. Similar shapes are figures with the same shape but not always the same size.



ENGAGE


Students, I want you to look at those figures above and examine them closely.
What do they have in common?
How are they different or would you say they are all the same?
What are the reasons for your answers?

Ok, I want you to examine the ones below.

Are you in agreement with the boys? Or they should have said 3 equal sides instead of 2?
Let's compare the triangles at the bottom with those above.

SIMILARITIES                                                                     DIFFERENCES
*Both sets are triangles                                                    * Bottom are same sizes but top ones are         *All have 3 angles                                                              different sizes
                                                                                         *all angles at the bottom ones are the same                                                                                                sizes but the angles above are different
                                                                               

EXPLORE

Ok children, today we are going to look at a new term to describe shapes that are exactly the same just like those triangles at the bottom. This is called CONGRUENT. Let us all spell the word together.

I want you to listen to the video clip below, which will explain more about this new term. Get your note pads for note taking.

Listen to this video clip .

EXPLAIN

Now what did you learn?
What is meant by congruency?
Can shapes be similar but not congruent?
When can two shapes be considered congruent?

EXTEND

Look at these shapes below. Without using a ruler, how could you prove if these shapes are congruent to their pairs?
👍- Of course we could simply cut them out and try to fit them over each other. You can print them and try the activity.



Now I'm sure you remember when we did the topic REFLECTION. I want you to extend yourselves. A reflected image is shown in the second quadrant. I want you to show what the original shape will look like in the first quadrant. Do you think they will both be considered congruent? Of course. Just ensure that you perform this task well! Use your graph paper.




EVALUATE

#1  Choose the shapes that are congruent to each other.


#2




#3.





#4




#5
Find the pairs of congruent shapes.