Exercise 12 Page 597

We are asked to determine if the yearbook photo is a dilation of the original photo. To do this, we will compare a ratio of widths and a ratio of lengths. If they turn out to be equal, then we have a dilation. Yearbook's Width/Original Width? =Yearbook's Length/Original Length Let's evaluate these ratios using the given dimensions. We will start with the ratio of widths.

The ratio of widths is 53. Now we will evaluate the ratio of lengths.

The ratio of lengths is also 53. Yearbook's Width/Original Width? =Yearbook's Length/Original Length ⇓ 5/3=5/3 Since the ratios are equal, the yearbook photo is a dilation of the original photo, and the scale factor is 53.