First, notice that Ryan and its shadow form a right triangle with the following measures:
and with the tree, we have the following triangle:
since both triangles are similar, we can write the following proportions:
[tex]\frac{x}{6}=\frac{28}{12}[/tex]where 'x' represent the height of the tree. Solving for 'x', we get:
[tex]\begin{gathered} \frac{x}{6}=\frac{28}{12} \\ \Rightarrow x=\frac{28}{12}\cdot6=\frac{28\cdot6}{12}=\frac{168}{12}=14 \\ x=14ft \end{gathered}[/tex]therefore, the height of the tree is 14 feet