Chapter 13: Problem 85
Find the coordinates of the vertex and the direction in which each parabola opens. A. \(y=8(x-3)^{2}+6\) B. \(x=8(y-3)^{2}+6\)
Short Answer
Expert verified
A: Vertex is (3, 6), opens upwards; B: Vertex is (6, 3), opens to the right.
Step by step solution
01
Identify the Vertex Form
The vertex form of a parabola equation can help us quickly identify the vertex coordinates. For the equation \( y = a(x-h)^2 + k \), the vertex is at \((h, k)\). Likewise, for \( x = a(y-k)^2 + h \), the vertex is at \((h, k)\).
02
Determine the Vertex of Equation A
The given equation is \( y = 8(x-3)^2 + 6 \). This matches the vertex form \( y = a(x-h)^2 + k \), where \( h = 3 \) and \( k = 6 \). Therefore, the vertex is \((3, 6)\).
03
Determine the Direction of Opening for Equation A
Since the equation is in the form of \( y = a(x-h)^2 + k \) and the coefficient \( a = 8 \) is positive, the parabola opens upwards.
04
Determine the Vertex of Equation B
The equation is \( x = 8(y-3)^2 + 6 \). This fits the form \( x = a(y-k)^2 + h \), where \( h = 6 \) and \( k = 3 \). Therefore, the vertex is \((6, 3)\).
05
Determine the Direction of Opening for Equation B
In this case, the form \( x = a(y-k)^2 + h \) is used, where the coefficient \( a = 8 \) is positive, meaning the parabola opens to the right.
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.
Vertex Form
The vertex form of a parabola is an elegant way to express the equation of a parabola because it allows us to easily identify important features of the parabola. There are two main types of parabolic equations that we encounter:
- For the equation of the form \(y = a(x-h)^2 + k\), the vertex is located at the point \((h, k)\). This type of equation describes a parabola that opens either upwards or downwards, depending on the value of \(a\).
- For the equation of the form \(x = a(y-k)^2 + h\), the vertex is at the point \((h, k)\) as well, but this describes a parabola that opens either to the right or left, again depending on \(a\).
Direction of Opening
Understanding the direction in which a parabola opens is fundamental to grasping its geometry. The direction of opening is determined primarily by the coefficient \(a\) in the vertex form. Here’s how it works:
- For a vertical parabola given by \(y = a(x-h)^2 + k\):
- If \(a > 0\), the parabola opens upwards.
- If \(a < 0\), the parabola opens downwards.
- For a horizontal parabola expressed as \(x = a(y-k)^2 + h\):
- If \(a > 0\), it opens to the right.
- If \(a < 0\), it opens to the left.
Parabolic Equations
Parabolic equations describe curves known as parabolas, which are U-shaped or directionally similar curves. They feature prominently in various mathematical applications and scenarios. Parabolas can be aligned either vertically or horizontally:
- In vertical parabolas, the equation is written as \(y = a(x-h)^2 + k\) and the graph is symmetric around the vertical axis passing through the vertex.
- In horizontal parabolas, the form \(x = a(y-k)^2 + h\) means the graph is symmetric about a horizontal axis through the vertex.