Square OABC is drawn on a centimetre grid. O is(0,0) A is(3,0) B is(3,3) C is(0,3). Write down how many invariant points there are on the perimeter of the square, when OABC is enlarged, scale factor 2, centre (0,0)

1 point. O (0,0)

Step-by-step explanation:

Hi

Invariant points are those points who remain on the same location after a given transformation.

1.  Plotting OABC we have it below:

2. Whenever we dilate centered, the image O'A'B'C' will be determined by the following points:

Since the Scale factor is (2)

3. Check it out O'A'B'C' below

4. On the perimeter of O'A'B'C' (enlarged OABC) we have left 1 point invariant.

Step-by-step explanation:

There are 30 teachers for the principal to choose from initially. After the principal chooses one, there will be 29, 28, 27, and so on.

Since the principal is only choosing 3, there are permutations. However, the order of which the principal chooses the teachers does not matter. In other words, without loss of generality, let the name of three of the teachers be Adam, Bernie, and Carla. Regardless of whether the principal chooses Adam then Bernie then Carla or Carla then Adam then Bernie, etcetera, the same three teachers are still being chosen.

Thus, we must divide by the number of ways you can rearrange three distinct teachers, which is .

Therefore, the desired answer is