Dilation and Scale Factors in Geometry

The video tutorial by Mrs. Apia covers dilations on the coordinate plane, focusing on the multiplicative effect of scale factors when the center of dilation is the origin. Through various examples, students learn to calculate the coordinates of dilated points by multiplying the original coordinates by the scale factor. The tutorial also explores dilations with negative coordinates and the dilation of a triangle, emphasizing the relationship between original and dilated points.

What is the effect of a scale factor on a point when the center of dilation is the origin?

• It divides each coordinate by the scale factor.

• It subtracts the scale factor from each coordinate.

• It multiplies each coordinate by the scale factor.

• It adds the scale factor to each coordinate.

In Example 1A, what are the coordinates of the dilated point A' when the scale factor is 2?

• (12, 8)

• (3, 2)

• (6, 4)

• (9, 6)

In Example 1B, what happens to the coordinates of point A when dilated by a scale factor of 4?

• They remain the same.

• They are halved.

• They are quadrupled.

• They are doubled.

What was the original point used in the review of Lesson 5?

• (7, 6)

• (3, 3)

• (5, 2)

• (2, 5)

In Example 2, what is the scale factor used to verify the method of finding dilated coordinates?

• 2

• 11/7

• 3

• 4

In Example 3, what is the predicted location of A' when A is (-2, 3) and the scale factor is 3?

• (-6, 9)

• (-3, 6)

• (-9, 6)

• (-6, 3)

What is the multiplicative relationship between a point and its dilation?

• The coordinates are multiplied by the scale factor.

• The coordinates are divided by the scale factor.

• The coordinates are subtracted from the scale factor.

• The coordinates are added to the scale factor.

In Example 5, what happens to triangle ABC when dilated by a scale factor of 1/3?

• It expands.

• It contracts.

• It remains unchanged.

• It rotates.