If you use a scale factor of. 1/5 to create a circle radius 18cm, What is the radius of the original circle dilated
To produce a dilated image that is smaller than the original image, you need to use a scale factor between 0 and 1.
If you use a scale factor of 0.5, for example, the dilated image will be half the size of the original image. Similarly, if you use a scale factor of 0.25, the dilated image will be one-fourth the size of the original image. Any scale factor between 0 and 1 will result in a smaller dilated image.
To find the radius of the original circle dilated, you need to multiply the radius of the dilated circle by the reciprocal of the scale factor.
The scale factor is 1/5, so the reciprocal is 5/1 or simply 5.
The radius of the dilated circle is 18 cm, so to find the radius of the original circle, you multiply 18 by 5.
Radius of the original circle = 18 cm * 5 = 90 cm