Answer:
The kite is 35.71 m high from Emily.
Explanation:
Supposing that the kite's string is a straight line, Anna, Emily and the kite form a right triangle (see the figure below).
A right triangle follows the Pythagoras' theorem (or Pythagorean theorem):
, where c is the hypotenuse and a and b, the other two sides (catheti).
Since the opposite side to the right angle (90°) is the hypotenuse, in this case, c = 50 m, and we know that d = 35 m (the distance from Anna to Emily, or vice versa), we can rewrite the equation for this problem as follows (see figure below):
, or

Likewise, the height h is the unknown value or the height of the kite from Emily (or one leg of the right triangle).
.
, which is approximately:
m or
m.
That is, the kite is approximately 35.71 m high above Emily.