Calculate Ascending Area of y=-(x+3)² : Quadratic Function Analysis

Find the ascending area of the function

$y=-(x+3)^2$

We start by recognizing the function $y = -(x+3)^2$, which is a parabola that opens downwards with its vertex at $(-3, 0)$. In the vertex form of a parabola $y = a(x - h)^2 + k$, the values increase until reaching the vertex if the parabola opens downwards.

The expression $y = -(x+3)^2$ indicates that as $x$ moves towards $-3$ from the left, the function's values increase until reaching the vertex since the parabola is opening downwards.

Therefore, the interval over which the function is increasing corresponds to $x < -3$.

Thus, the ascending area of the parabola described by the function $y = -(x+3)^2$ is for $x < -3$.