Answer:
Divide by 2 and square the result
Explanation:
To complete the square of y = x² + bx, divide b by 2 and square the result, then add to both sides.
For example, if y = x² + 2x, then you add (2/2)² = 1 to both sides.
y + 1 = x² + 2x + 1
y + 1 = (x + 1)²
y = (x + 1)² − 1