CONGRUENT FIGURES
|
Unit Overview
In this unit, students will define and identify figures that are congruent, and they will understand the relationship between the corresponding parts of congruent figures.
Congruent Figures
Two objects are congruent if they have the same size and shape. The symbol for congruent is (≅). Two figures are congruent if and only if their vertices can be matched so that corresponding parts of the figures are congruent. The corresponding parts are the angles and sides. When writing which figures are congruent, be sure to write the vertices in the same order.
Example - Congruent Angles & Sides
 |
Let's Practice - Congruent Angles & Sides
1.) The corresponding parts of two congruent triangles are marked in the image below. Write the congruent angles and sides.
|
 Move the mouse cursor over the figure to check the answer. |
2.) Complete each congruence statement by naming the corresponding side.
|
| Move the mouse cursor over the figure to check the answer. |
|
| Move the mouse cursor over the figure to check the answer. |
|
5.) The two quadrilaterals are congruent. Which side in quadrilateral WXYZ corresponds to BC in quadrilateral ABCD?
|
Congruent v. Similar Figures
There is one major difference between a congruent figure and similar figure. A congruent figure have the same shape and the same size. On the other hand, similar figures have the same shape, but not the same size. They must have the same ratio of side length. Remember, that corresponding parts are the sides or angles that have the same position.
Example
Step 1 à Determine if the two figures are similar or congruent
Step 2 à Look at the figures carefully
Step 3 à If the shape is same than they are similar
Step 4 à If the size is also same than they are congruent too
Figure above is similar
Here is another example. How are the figures below related?
Use the same step strategy above to determine the answer.
The pair of shapes given are not of the same shape or size. The two figures are neither similar nor congruent.
Let's Practice - Congruent v. Similar
6.) Determine if the shapes shown are similar, congruent or neither.
 |
| Move the mouse cursor over the figure to check the answer.
|
7.) Determine if the shapes shown are similar, congruent or neither.
 |
| Move the mouse cursor over the figure to check the answer.
|
8.) Determine if the shapes shown are similar, congruent or neither.
 |
| Move the mouse cursor over the figure to check the answer.
|
9.) Determine if the shapes shown are similar, congruent or neither.
 |
| Move the mouse cursor over the figure to check the answer.
|
10.) Determine if the shapes shown are similar, congruent or neither.
|
| Move the mouse cursor over the figure to check the answer. |
Summary
Congruent Figures
Similar Figures
Let's Practice - Summary
11.) If JKLM and NOPQ are congruent quadrilaterals, which angle in JKLM matches with ∠P?
|
| Move the mouse cursor over the figure to check the answer. |
Use the image below to answer questions 12 and 13.
|
| Move the mouse cursor over the question to check the answer. |
|
| Move the mouse cursor over the question to check the answer. |
14.) ΔMNO and ΔSTR are congruent triangles. Find the measure of ∠O.
|
| Move the mouse cursor over the question to check the answer. |
15.) ΔMNO and ΔSTR are congruent triangles. Find the measure of ∠O.
|
| Move the mouse cursor over the figure to check the answer. |
 |
|
 Click on the icon to the left to practice labeling corresponding parts. |
 Click on the icon to the left to watch a video about Congruent and Similar Triangles. |
