To find the scale factor used by Leo to enlarge the original pentagon from sides measuring 3 centimeters to sides measuring 8 centimeters, we can set up the following ratio:
\[ \text{Scale Factor} = \frac{\text{New Side Length}}{\text{Original Side Length}} = \frac{8 \text{ cm}}{3 \text{ cm}} \]
Now, we perform the division:
\[ \text{Scale Factor} = \frac{8}{3} \]
To express this as a mixed number:
\[ \frac{8}{3} = 2 \frac{2}{3} \]
Thus, the scale factor Leo used to create the photograph from the original pentagon is:
2 2/3