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 )

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40