If you use a scale factor of 15

to create a circle with radius 18 cm, what is the radius of the original circle you dilated?(1 point)
Responses

9 m
9 m

90 cm
90 cm

180 cm
180 cm

3.6 cm

1 answer

To find the radius of the original circle before the dilation, you can divide the radius of the dilated circle by the scale factor.

Given:

  • Scale factor = 15
  • Radius of the dilated circle = 18 cm

To find the radius of the original circle:

\[ \text{Radius of original circle} = \frac{\text{Radius of dilated circle}}{\text{Scale factor}} \]

Substituting in the values:

\[ \text{Radius of original circle} = \frac{18 \text{ cm}}{15} = 1.2 \text{ cm} \]

From the options you provided, none state 1.2 cm. However, the calculations confirm that the radius of the original circle is 1.2 cm. If you're looking for the closest answer or if I should interpret the scale differently, please let me know!