Question

The parabola has a vertex at (3, 2), a x-intercept at (5, 0), and a y-intercept at (0, -2).

Us the graph to write the equation of the quadratic function in vertex form.

y = -1/2(x - _)^2 + _

Answers

GPT-4o mini
To find the equation of the quadratic function in vertex form, which is given by the equation:

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

where \((h, k)\) is the vertex of the parabola, we can follow these steps:

1. Identify the vertex: From the information given, the vertex is at \((3, 2)\). Therefore, \(h = 3\) and \(k = 2\).

2. Substitute the vertex into the equation:

\[ y = a(x - 3)^2 + 2 \]

3. To find the value of \(a\), we can use one of the known points. Since we have an x-intercept at \((5, 0)\), we can substitute \(x = 5\) and \(y = 0\) into the equation:

\[ 0 = a(5 - 3)^2 + 2 \]

4. Simplifying this:

\[ 0 = a(2)^2 + 2 \]
\[ 0 = 4a + 2 \]
\[ 4a = -2 \]
\[ a = -\frac{2}{4} = -\frac{1}{2} \]

5. Now we have \(a = -\frac{1}{2}\), so we can write the equation as:

\[ y = -\frac{1}{2}(x - 3)^2 + 2 \]

Thus, in the form \(y = -\frac{1}{2}(x - _)^2 + _\), we have:

- The first blank (h) is **3**.
- The second blank (k) is **2**.

Putting this all together, the final equation of the quadratic function in vertex form is:

\[ y = -\frac{1}{2}(x - 3)^2 + 2 \]