(Make a shortcut so the problem appears easier.)
Shortcut: x^2/3 = x^1/3 = y^2
(Substitute shortcut in the x^2/3 spot.)
x^2/3 = 19
y^2 = 19
Translate back through the shortcut
x^1/3 = 19
To get x by itself, you would cube it
(x^1/3)^3 = (19)^3
x = 6859
Answer:
x = 6,859