Answer:
4
Explanation:
The first thing you need to do is find the geometric mean between 2 and 6.
That is the ratio that they hypotenuse of the largest triangle is divided into.
altitude^2 = 2* 6
altitude^2 = 12
altitude = sqrt(12)
altitude = 2 sqrt(3)
Now use Pythagorus to find x
x^2 = 2^2 + altitude^2
x^2 = 2^2 + 12
x^2 = 4 + 12
x^2 = 16
x = 4