=4(4x+2y+x-y)
=4*4x+4*2y+4*x-4*y
=16x+8y+4x-4y
=16x+4x+8y-4y
=20x+4y
donc la bonne reponse est la 3
4(5x+y)*
=4*5x+4*y
=20x+4y
Answer:
86.63 ft
Step-by-step explanation:
The tangent relation applies.
Tan = Opposite/Adjacent
tan(77°) = (tree height)/(20 ft)
tree height = (20 ft)·tan(77°) ≈ 86.63 ft
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<em>Additional comment</em>
It is somewhat problematic for Bob to see the top of a white pine tree at that angle of elevation. His view would likely be obscured by the branches of the tree.
Answer:
21.99ft
Step-by-step explanation: