Let us convert the standard form into vertex form.
1) Complete the squares. Isolate x² and x terms. y - 6 = x² + 12x 2) Create the perfect square trinomial. Whatever number is added on one side must also be added on the other side.
y - 6 + 36 = x² + 12x + 36 y + 30 = (x + 6)² y = (x + 6)² - 30 ← Vertex form To check:
y = (x + 6) (x + 6) - 30 y = x² + 6x + 6x + 36 - 30 y = x² + 12x + 6
The zero that could be added to the given function is 36, -36
