91.7k views
3 votes
Use the parabola tool to graph the quadratic function f(x) =2x2 - 12x+11 graph the parabola by first plotting its vertex and then plotting a second point on the parabola.

User Eldblz
by
7.6k points

1 Answer

3 votes

Answer:

  • vertex: (3, -7)
  • point: (4, -5)

Explanation:

You want the vertex and another point on the parabola f(x) = 2x² -12x +11.

Vertex

The equation can be put into vertex form as follows:

f(x) = 2(x² -6x) +11 . . . . . . . factor the leading coefficient from the variable terms

f(x) = 2(x² -6x +9) +11 -2(9) . . . . add (6/2)² = 9 inside parentheses, subtract the same amount outside

f(x) = 2(x -3)² -7 . . . . . . . . simplify to vertex form

Comparing this to the vertex form equation ...

f(x) = a(x -h)² +k

we see that a=2, h=3, k=-7.

The vertex is (h, k) = (3, -7). This is one point on the parabola.

A second point

We can use a value for x that is near the value of h to obtain another point on the parabola without much work. Using x = 4, we have ...

f(4) = 2(4 -3)² -7 = 2(1) -7 = -5

Another point is (x, y) = (4, -5).

You can plot the vertex (3, -7) and the point (4, -5) to obtain your graph of the parabola using the parabola tool.

__

Additional comment

The points and the parabola are shown in the attached graph.

<95141404393>

Use the parabola tool to graph the quadratic function f(x) =2x2 - 12x+11 graph the-example-1
User Jon Colverson
by
8.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories