Tree = x
Shadow = x - 35
Distance from top of tree
to end of shadow = x + 5
So x^2 + (x -35)^2 = (x + 5)^2
x^2 +(x^2 - 70x + 1225) = (x^2 + 10x + 25)
Combine and collect like terms.
x^2 - 80x + 1200
(x - 20)(x - 60)
So either x = 20 or x = 60
As the shadow = (x - 20) I would
discount x = 20
Tree height = 60ft
Tree's shadow =25
Distance from top of
tree to tip of shadow.
= 65