Why do single-crooked creatures look exactly like the parent cell?

 The indigesti- size until the whole interior is pretty well filled ble remainder is then ... little, and in one place is bent into the form of a mouth—very much like that of a beaker. ... One can see the creature go through the same movements if the vessel in ... Each of these parts enlarges and becomes exactly like the parent animal.

Explanation:

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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