Open Up 8th Grade Unit 2

Front

What is a scale factor in dilation?

Back

A scale factor is a number that scales, or multiplies, the dimensions of a shape during dilation. It determines how much larger or smaller the image will be compared to the original shape.

Front

If the scale factor is ½, what does it mean for the size of the shape?

Back

It means the new shape will be half the size of the original shape.

Front

What does it mean to dilate a point using a center of dilation?

Back

To dilate a point means to move it away from or towards the center of dilation by a certain scale factor, resulting in a new point.

Front

What is the result of dilating a shape by a scale factor greater than 1?

Back

The shape will increase in size.

Front

What is the result of dilating a shape by a scale factor less than 1?

Back

The shape will decrease in size.

Front

What is the relationship between similar shapes and scale factors?

Back

Similar shapes have the same shape but different sizes, and their corresponding sides are proportional, which is determined by the scale factor.

Front

What does it mean for two shapes to be congruent?

Back

Two shapes are congruent if they have the same size and shape, meaning all corresponding sides and angles are equal.

Front

How do you determine if two shapes are similar?

Back

Two shapes are similar if their corresponding angles are equal and their corresponding sides are in proportion.

Front

What is the image of a rectangle under dilation with a scale factor of 2?

Back

The image will be a rectangle that is twice the length and twice the width of the original rectangle.

Front

If triangle ACB is dilated to triangle ADE with a scale factor of ½, what happens to the area?

Back

The area of triangle ADE will be ¼ the area of triangle ACB because area scales by the square of the scale factor.