Explanation:
x/y = y/z = z/x
x = y²/z = zy/x and y = z²/x
x = y²/z
putting this into the 3rd part of the original equation :
z/x = z/ y²/z = z²/y²
now using the y identity of the second part there :
y = z²/x
z²/y² = z² / z⁴/x² = x²/z² (= z/x per previous equation)
so,
x²/z² = z/x
x³/z³ = 1
x/z = 1
x = z
then
y/z = y/x = z/x (= 1)
and therefore,
y/x = z/x meaning
y = z (and therefore = x)
so,
x = y = z