There is a small island in the middle of a 100m wide river. There is a tall tree on island. Points P and Q are points directly opposite each other on the two banks, and in line with the tree. If the angles of elevation of the top of the tree at P and Q are 30° and 45°, find the height of the tree. (A) 25.5 m (B) 36.6 m (C) 45.6 m (D) 35.5 m

geometry: triangles

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584

50-60=10

step-by-step explanation:

i think the answer is true

step-by-step explanation:

i believe so, according to my "strange" way of figuring out weird math problems like this.