compete curre chewe fonetion a) $y=x^{2}+4 x$

Step 1 ：Given the quadratic function: \(y = x^2 + 4x\)

Step 2 ：Find the complete square form by adding and subtracting the square of half of the coefficient of the x term:

Step 3 ：\(a = 1\)

Step 4 ：\(b = 4\)

Step 5 ：\(c = \frac{b}{2} = 2\)

Step 6 ：\(y = (x + 2)^2 - 4\)

Step 7 ：\(\boxed{y = (x + 2)^2 - 4}\)