Answer:
From the diagram you can see that we have constructed a right triangle, with height A and base 15.Length of shadow = 15 feet.Height of flagpole = A.We know the angle of elevation is 40∘. Using this angle and the tangent ratio, we can find A.tan(40∘)=oppositeadjacent=A15∴tan(40∘)=A15Rearranging:A=15tan(40∘)By calculator:A=12.59 feet. ( 2 d.p.)
