F(x)=-x²-2x-8 determine the vertex

vertex = (- 1, - 7 )

Step-by-step explanation:

Given a parabola in standard form, f(x) = ax² + bx + c (a ≠ 0 )

Then the x- coordinate of the vertex is

= -

f(x) = - x² - 2x - 8 ← is in standard form

with a = - 1 and b = - 2, then

= - = - 1

Substitute x = - 1 into f(x) for corresponding y- coordinate

f(- 1) = - (- 1)² - 2(- 1) - 8 = - 1 + 2 - 8 = - 7

vertex = (- 1, - 7 )

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

answer: i wpould go with c

step-by-step explanation: