The tree is 52.8 feet, since the hypotenuse is only part of the tree, you have to add 12, since then it would equal the total height of the tree.
a^2+b^2=c^2
12^2+ 39^2=c^2
144+1521= 1665
√1665
= 40.8
40.8 + 12
= 52.8 feet
There are several approaches.
(5/3)x^2 - 5 = 0 has the coefficients a=5/3, b=0 and c = -5.
Thus, the quadratic formula would be appropriate here:
-0 plus or minus sqrt(0^2 - 4(5/3)(-5) )
x = -------------------------------------------------------
2(5/3)
plus or minus sqrt(100/3)
= ------------------------------------
10/3
3 10
= ------* ----------- = sqrt(3) (answer)
10 sqrt(3)
7/25 because you can divide everything. Y 3