Complete the square to re-write the quadratic function in vertex form: y = x2 + 4x – 9

Mathematics

2 answers:

Alona [7]2 years ago

5 0

Answer: − 2 ± √ 13

Step-by-step explanation:

(-b±√(b²-4ac))/(2a)

Plug in and solve.

Helen [10]2 years ago

3 0

Answer:

y = (x + 2)² - 13

Step-by-step explanation:

y = x² + 4x - 9

To complete the square

add/ subtract ( half the coefficient of the x- term)² to x² + 4x

y = x² + 2(2)x + 4 - 4 - 9

= (x + 2)² - 13 ← in vertex form

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