Answer:
y = (x + 4)² + 9
Step-by-step explanation:
y = x² + 8x + 25
y = (x² + 8x + ___) + 25 - ___
To complete the square, take half of the coefficient of the x term and square it. You add it inside the parentheses and subtract it at the end.
Take half of 8, which is 4. Square 4 to get 16. 16 completes the square, so add 16 inside the parentheses, and subtract 16 at the end.
y = (x² + 8x + 16) + 25 - 16
y = (x + 4)² + 9
