Dilations of a triangle are congruent to the original triangle, if the corresponding angles are congruent,

Hello i need some with trigonometric substitutions. [tex]\int\limits^a_b {x} \, dx[/tex]

Ineed if you could explain and give me the answer you! this needs done

Aman is 6 feet 3 inches tall. the top of his shadow touches a fire hydrant that is 13 feet 6 inches away. what is the angle of elevation from the base of the fire hydrant to the top of the man's head?