Answer: 53.1ft
Explanation:
We can draw a triangle rectangle.
Where the distance between the man and the tree is one cathetus, (the vertex is on the man's eyes)
The tree itself is the other cathetus, and the line that connects the man's eyes and the tip of the tree is the hypotenuse.
We know that:
The angle at the vertex of the man's eyes is 67°
And the adjacent cathetus, the distance between the man and the tree, is 20ft.
Then using the relation:
Tan(A) = (opposite cathetus)/(adjacent cathetus)
We can find the height of the treee:
Tan(67°) = X/20ft
Tan(67°)*20ft = X = 47.1ft
But remember that this is measured from the mans eye's, and the man's eyes are 6ft away from the ground.
Then the height of the tree is 47.1ft + 6ft = 53.1ft