Answer:
7
Step-by-step explanation:
The function can be written in vertex form as ...
f(x) = -(x +1)^2 +7
The vertex is then identifiable as (-1, 7). The y-coordinate is 7.
_____
Vertex form is ...
f(x) = a(x -h)^2 +k
where "a" is the vertical scale factor, and (h, k) is the vertex point. It is convenient to arrive at this form by factoring "a" from the first two terms, then adding and subtracting the square of the remaining x-coefficient inside and outside parentheses.
f(x) = -(x^2 +2x) +6
f(x) = -(x^2 +2x +1) + 6 -(-1) . . . . completing the square
f(x) = -(x +1)^2 +7 . . . . . . . . . . . . vertex form; a=-1, (h, k) = (-1, 7)
