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Dilations

Dilate this triangle by a scale factor of 2.

Is this what you got?

Why does the location matter? Aren't both of the big triangles two times larger than the small triangle?

Not only is the image two times bigger, it is two times further away from the origin! That is why the location mattered.

Let's examine this by looking at the slope of each line.

What if it is dilated by a scale factor of 3? It is three times bigger and three times further away from the origin.

How would you dilate this triangle by a scale factor of 2 about (-1, 3)?

Dilate the First Point

Dilate the Second Point

Dilate the Third Point

Examine Slopes.

Can you identify the center of dilation based on the image and pre-image?

We know the scale factor is 2, but what is unique about the slope of the lines connecting the image and pre-image points?

Examine Slopes.