Respuesta :
Answer:
see explanation
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
To obtain this form use the method of completing the square
add/ subtract (half the coefficient of the x- term)² to x² + 8x
y = x² + 2(4)x + 4² - 4² + 7 ← complete the square
= (x + 4)² - 16 + 7
= (x + 4)² - 9 ← in vertex form
with vertex = (- 4, - 9)
The minimum value is the y value of the vertex
Minimum value = - 9 when x = - 4
