Chapter 10: Problem 7
Name the conic or limiting form represented by the given equation. Usually you will need to use the process of completing the square. $$ y^{2}-5 x-4 y-6=0 $$
Short Answer
Expert verified
The given equation represents a parabola.
Step by step solution
01
Rearrange the Equation
Start with the given equation \( y^2 - 5x - 4y - 6 = 0 \). Isolate terms involving \( y \) on one side: \( y^2 - 4y = 5x + 6 \).
02
Complete the Square for y
To complete the square for \( y \), take half the coefficient of \( y \) (which is -4), square it, and add it to both sides. Half of -4 is -2, and \((-2)^2 = 4\). Add 4 to both sides: \( (y^2 - 4y + 4) = 5x + 10 \).
03
Simplify the Equation
The left side becomes a perfect square: \((y - 2)^2 = 5x + 10 \).
04
Rearrange into Standard Form
Subtract 10 from both sides to get \( (y - 2)^2 = 5x + 10 - 10 \), which simplifies to \( (y - 2)^2 = 5x \).
05
Identify the Conic Section
The equation \((y - 2)^2 = 5x \) is in the form \( (y-k)^2 = 4p(x-h) \), which is the standard form of a parabola. Thus, the conic section is a parabola.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Completing the Square
Completing the square is a useful algebraic technique that transforms a quadratic equation into a form that is easier to work with.
For quadratic expressions resembling (\(ax^2 + bx + c = 0\)), completing the square involves creating a perfect square trinomial from the quadratic terms. This helps to easily solve or manipulate the equation.
For quadratic expressions resembling (\(ax^2 + bx + c = 0\)), completing the square involves creating a perfect square trinomial from the quadratic terms. This helps to easily solve or manipulate the equation.
- Start by rearranging terms to isolate the quadratic and linear terms on one side of the equation.
- Look at the coefficient of the linear term (the term with only a single variable). Take half of this coefficient, which provides the magic number needed for completing the square.
- Square this magic number and add it to both sides of the equation. This creates a perfect square trinomial on one side, turning it into a binomial squared.
Parabola
A parabola is one of the simplest yet fascinating figures in conic sections. It represents the path followed by a projectile under uniform gravitational force, among other real-world applications.
The parabola's shape is defined as the set of all points that are equidistant from a fixed point (called the "focus") and a line (called the "directrix").
The parabola's shape is defined as the set of all points that are equidistant from a fixed point (called the "focus") and a line (called the "directrix").
- Unlike circles, parabolas have an open curve structure.
- They are typically represented algebraically by the vertex form \(y = a(x-h)^2 + k\) or \((y-k)^2 = 4p(x-h)\).
Standard Form of a Parabola
The standard form of a parabola helps to quickly identify its essential features, such as the vertex, axis of symmetry, and the direction of opening. Generally represented as y = a(x-h)^2 + k for vertical parabolas and(x-h)^2 = 4p(y-k) for horizontal parabolas,
it simplifies the process of analyzing parabolic equations.
it simplifies the process of analyzing parabolic equations.
- The vertex is the point \((h, k)\) where the parabola changes direction.
- The parameter 4p describes the distance from the vertex to the focus as well as to the directrix, allowing us to determine how "wide" or "narrow" the parabola appears.