Similar Triangles
Below are some animations to help you write your own tests to prove two triangles are similar.
You are to read the instructions carefully and answer all questions in your exercise book. If you are having trouble or unsure about something, first ask the person next to you then a teacher.
Once completed, see one of the teachers.
Test 1
Feel free to move the locations of the BLACK VERTICES of either triangle before slowly dragging the slider. Pay careful attention to what happens as you do.
Questions:
1. Describe in your own words what is happening.
2. How many angles were identified in the pink triangle? Are they equal to the white triangle?
3. Write the test to prove these two triangles are similar? Hint: Use the answers from above to help you
Test 2
Divide a and d, b and e, c and f. What do you notice?
Write a test based on your findings to show that two triangles, like below, are similar. Call this test 2.
Test 3
In the animation below, you'll find two triangles.
The black angle in the green triangle is congruent to the black angle in the pink triangle.
In the green triangle, the black angle is the included angle between sides a and b.
In the pink triangle, the black angle is the included angle between sides ka and kb.
Interact with the applet below for a few minutes. As you do, be sure to move the locations of the green triangle's BLACK VERTICES and the location of the BIG X.
You can also adjust the value of k by using the slider or by entering a value between 0 & 1.
Questions:
1. What does it mean by 'included angle'?
2. What does k represent?
3. What happens to the pink triangle when the value of k increases?
4. Complete this statement:
If two sides of one triangle are p_____________ to two sides of another triangle and the _____________ angles are equal, then the triangles are similar.
INSTRUCTIONS FOR TEST 4
Test 4
You will need an instruction sheet from the teacher in order to produce two right angled triangles.
Follow those instructions and answer the questions from the worksheet using this applet to build the triangles.
STOP HERE ONCE YOU HAVE FINISHED THE ABOVE TASK
Let a teacher know once you have completed the above task. So we can discuss as a class.
Complete the below worksheet once we have done examples together as a class.
You are to finish this worksheet in class as well as textbook questions from EX 4D Q8-Q12. If it has not been completed, the rest will be for homework as well as Review Set 4A and 4B.
