Jackson uses a credit card to purchase new living room furniture. He purchases a sofa that costs $865, 2 chairs that are $380 each, coffee and end tables for $425 and a set of lamps for $130. He must also pay 8% tax for the purchase. The credit card charges an interest rate of 17.9%. If he pays for this credit card loan in 24 months, what is the total cost to repay the loan? Use and online calculator to solve.

The image attached shows a diagram of the problem. 
We first want to find the angle, or rather the tangent of the angle, formed by the light, the pole, and the ray of light that travels across the girl's noggin to the tip of her shadow:

tan (x) = opposite/ adjacent
tan (x) = 6 / 7
We know that the tangeant of this angle is 6/7

We can then apply this ratio to the total length from the pole to her shadow:
6/7 = x / 12        Cross multiply
7x = 72
x = 72/7 = 10.29

The total length from the base of the pole to her shadow is 10.29 feet. 
She is 6 feet from the pole, so her shadow is:
10.29 - 6 = 4.29 feet long