Is there a question here somewhere?
Y = 0.8
4x + 8y = 40
4x + 8*(0.8) = 40
4x + 6.4 = 40
4x = 40 - 6.4
4x = 33.6
x = 8.4
Since y=y. set the equations equal to each then solve
2x + 1 = -x + 4
+x +x
3x + 1 = 4
-1 -1
3x = 3
/3 /3
x = 1
Draw a right triangle to represent the problem.
The vertical height of the triangle is 9 ft, and it represents the tree.
The horizontal length, at the bottom of the tree is ground level and has a length of 13 ft.
Let x = angle of elevation.
By definition,
tan x = 9/13 = 0.6923
x = arctan(0.6923) = 34.7 deg. = 35 deg (approx)
Answer: 35°
