Chapter 5: Problem 7
Solve each equation by graphing. If exact roots cannot be found, state the consecutive integers between which the roots are located. $$ -14 x+x^{2}+49=0 $$
Short Answer
Expert verified
The root is exactly at \(x = 7\).
Step by step solution
01
Rearrange the Equation
First, observe the equation given: \[-14x + x^2 + 49 = 0\]. We can rewrite it as follows: \[x^2 - 14x + 49 = 0\].This form is useful for recognizing that this is a quadratic equation.
02
Identify the Parabola
The equation \[x^2 - 14x + 49 = 0\] is a quadratic equation. In standard form, the parabola can be expressed as \[y = x^2 - 14x + 49\].This allows us to graph the function as a parabola.
03
Graph the Parabola
Plot the parabola given by the equation \[y = x^2 - 14x + 49\] on the graph. Note that the vertex of the parabola can be found using the vertex formula for a quadratic equation, \( x = \frac{-b}{2a} \), which gives \( x = \frac{14}{2} = 7 \). Thus, the vertex is at (7, 0).
04
Determine the Roots
Since the vertex is on the x-axis at \((7, 0)\), this means that the parabola touches the x-axis at this point and does not cross it. This indicates that there is exactly one root, which is \(x = 7\).
05
Conclude the Roots
Since the parabola only touches the x-axis at \(x = 7\) and does not cross it, we conclude that the exact root is \(x = 7\) and there are no other integer roots between which the roots are located.
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.
Parabola
A parabola is a U-shaped curve that can open upwards or downwards. It is defined by a quadratic function, which has the form \( y = ax^2 + bx + c \). The direction in which the parabola opens depends on the coefficient \( a \). For example:
- If \( a > 0 \), the parabola opens upwards.
- If \( a < 0 \), the parabola opens downwards.
Vertex Form
The vertex form of a quadratic equation is a powerful way to quickly understand the properties of a parabola. The vertex form is expressed as:\[y = a(x-h)^2 + k\]Here,
- \( (h, k) \) is the vertex of the parabola.
- \( x = h \) is the axis of symmetry.
- \( a \) determines the direction and the "width" of the opening.
Graphing Quadratics
Graphing quadratics is an effective visual method to find the roots of a quadratic equation. Here, you transform the equation into a parabolic shape on a graph. For example, when you have the equation \( y = x^2 - 14x + 49 \), you:
- Identify the vertex using \( x = \frac{-b}{2a} \). In this case, it is \( x = 7 \).
- Plot the vertex on the graph, which gives you an important reference point.
- Draw the symmetrical shape that extends from the vertex following the values decided by \( a \).