Aplane is at an altitude of feet above ground level. after 30 minutes, the plane rises by an altitude of feet. which of the following is true about the altitude of the plane after 30 minutes?

i think it is 70

step-by-step explanation:

geometry: triangles

solvers

lessons

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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