x is the short side of the triangle with hypotenuse (2+8)=10. x is the hypotenuse of the triangle with short side of length 2.
x/2 = 10/x . . . . ratio of hypotenuse to short side is the same for similar triangles x^2 = 20 . . . . . multiply by 2x x = √20 ≈ 4.47 . . . . . . . matches selection G
