A quadratic inequality opens upward, has a vertex at (−1,−1), passes through the point (0,1), and has a solid curve with shading below the curve.Write the quadratic inequality that represents the description.(1 point)The quadratic inequality that represents the description is $$.

1 answer

Given the information about the quadratic inequality, we know the following:

  1. The vertex of the quadratic is at \((-1, -1)\).
  2. The quadratic opens upward.
  3. It passes through the point \((0, 1)\).
  4. The inequality represents the region below the curve.

Let's express the quadratic in vertex form, which is given by:

\[ f(x) = a(x - h)^2 + k \]

where \((h, k)\) is the vertex. Substituting the vertex \((-1, -1)\):

\[ f(x) = a(x + 1)^2 - 1 \]

Next, we need to determine the value of \(a\). We know that the quadratic passes through the point \((0, 1)\):

\[ f(0) = a(0 + 1)^2 - 1 = 1 \]

Simplifying this equation:

\[ a(1)^2 - 1 = 1 \]

\[ a - 1 = 1 \]

\[ a = 2 \]

Now we can write the quadratic function:

\[ f(x) = 2(x + 1)^2 - 1 \]

To express it in standard form:

\[ f(x) = 2(x^2 + 2x + 1) - 1 = 2x^2 + 4x + 2 - 1 = 2x^2 + 4x + 1 \]

Since the shading is below the curve (the region where the quadratic is less than or equal to zero), the quadratic inequality is:

\[ 2x^2 + 4x + 1 \leq 0 \]

Thus, the quadratic inequality that represents the description is:

\[ \boxed{2x^2 + 4x + 1 \leq 0} \]