# Lesson 2Circle DilationsSolidify Understanding

Find the missing angle(s) in each of the figures.

### 4.

Find the angle of rotational symmetry for each regular polygon. (Note: A figure has rotational symmetry if it can be rotated by an angle between and so that the image coincides with the pre-image. The angle of rotational symmetry is the smallest angle for which the figure can be rotated to coincide with itself.)

## Set

### 7.

• If and are similar, locate the center of dilation.

• If the black, solid circle and the red, dotted circle are similar, locate the center of dilation.

• Which of the circles in the figure are similar? Justify your answer.

The radii for each of the circles in Figure 2 are , , and .

### 8.

What is the scale factor that dilates the circle with radius to the circle with radius ?

### 9.

What is the scale factor that dilates black, solid to ?

### 10.

If the circumference of black, solid is , what is the circumference of ?

## Go

Construct the line of reflection between the image and the pre-image. Then write the equation of the line of reflection.

Equation:

Equation:

### 13.

Draw the radius of the circle. (Note: The definition of radius requires you know or can locate the center of the circle. Construct the center before you draw the radius.)

### 14.

Draw the diameter of the circle. (Note: The definition of diameter requires you know or can locate the center of the circle. Construct the center before you draw the diameter.)