Answer:
(-4, 1)
Step-by-step explanation:
Start with -x^2-8x-15. Rewrite it as y = -1(x^2 + 8x + 15).
Focus on the terms x^2 + 8x; complete the square here:
x^2 + 8x + 16 - 16, or (x + 4)^2 - 16.
Put this back into y = -1(x^2 + 8x + 15) as follows:
y = -( (x + 4)^2 - 16 + 15)
Simplify this result: y = -(x + 4)^2 + 1
Compare this result to y = a(x-h)^2 + k. See that h = -4 and k = 1.
The coordinates of the vertex are (-4, 1).
