Math Problem Statement

Determine the quadratic function whose graph is given below. The vertex is (-2, -6), and the point (0, -2) lies on the parabola.

Solution

We are given a graph of a quadratic function, and we need to determine its equation. The graph shows a parabola with the following key points:

  • The vertex is at (2,6)(-2, -6).
  • Another point on the parabola is (0,2)(0, -2).

We can use the vertex form of a quadratic equation, which is:

f(x)=a(xh)2+kf(x) = a(x - h)^2 + k

where (h,k)(h, k) is the vertex. In this case, the vertex is (2,6)(-2, -6), so we can substitute these values into the equation:

f(x)=a(x+2)26f(x) = a(x + 2)^2 - 6

Next, we use the other given point (0,2)(0, -2) to find the value of aa. Substituting x=0x = 0 and f(x)=2f(x) = -2 into the equation:

2=a(0+2)26-2 = a(0 + 2)^2 - 6

Simplifying:

2=a(4)6-2 = a(4) - 6 2+6=4a-2 + 6 = 4a 4=4a4 = 4a a=1a = 1

Thus, the quadratic function is:

f(x)=(x+2)26f(x) = (x + 2)^2 - 6

Expanding this:

f(x)=(x2+4x+4)6f(x) = (x^2 + 4x + 4) - 6 f(x)=x2+4x2f(x) = x^2 + 4x - 2

So, the quadratic function that describes the graph is:

f(x)=x2+4x2f(x) = x^2 + 4x - 2

Would you like more details on how I expanded or solved this equation? Here are some related questions for further practice:

  1. How do you derive the vertex form of a quadratic equation?
  2. What are the steps to expand (x+2)26(x + 2)^2 - 6 into standard form?
  3. How can you determine the axis of symmetry for this quadratic function?
  4. How does the value of aa affect the shape of the parabola?
  5. Can you find the x-intercepts of this quadratic function?

Tip: When solving for the constant aa, always use another point on the graph to substitute into the equation.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Quadratic Functions
Vertex Form of Quadratic Equation

Formulas

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

Theorems

Vertex Theorem for Parabolas

Suitable Grade Level

Grades 9-12