Elementary Geometry for College Students (5th Edition)

The length of the shadow is $\approx 8.4$ ft.
Refer to the attachment: 1. Find the two missing angles in $\triangle ABC$ $\angle A = 90^{\circ}$(Given as a right angled triangle) $\angle B = 90 - 55 = 35^{\circ}$ $\angle C = 55^{\circ}$ (Alternate angles) 2. Use the sine law to solve for $x$ $\frac{x}{sin35} = \frac{12}{sin55}$ $x = \frac{12sin35}{sin55}$ $x = \frac{6.883...}{0.819...}$ $x = 8.402...$ft $x \approx 8.4$ft