Chapter 6: Problem 40
\(n^{2}-8 n-48=0\)
Short Answer
Expert verified
The solutions are \(n = 12\) and \(n = -4\).
Step by step solution
01
Identify the Type of Equation
The given equation is a quadratic equation in the standard form of \(an^{2} + bn + c = 0\), where \(a = 1\), \(b = -8\), and \(c = -48\).
02
Apply the Quadratic Formula
To solve the equation \(n^{2} - 8n - 48 = 0\), we can use the quadratic formula: \(n = \frac{-b \pm \sqrt{b^{2} - 4ac}}{2a}\).
03
Calculate the Discriminant
The discriminant \(b^2 - 4ac\) is calculated as follows: \((-8)^2 - 4(1)(-48) = 64 + 192 = 256\). The discriminant is positive, indicating two real roots.
04
Solve for the Roots
Plug the values into the quadratic formula: \[ n = \frac{-(-8) \pm \sqrt{256}}{2(1)} \] This simplifies to: \[ n = \frac{8 \pm 16}{2} \]Thus, the roots are \(n = \frac{24}{2} = 12\) and \(n = \frac{-8}{2} = -4\).
05
Verify the Solution
Check the values by substituting them back into the original equation. For \(n = 12\), \(12^{2} - 8(12) - 48 = 144 - 96 - 48 = 0\). For \(n = -4\), \((-4)^{2} - 8(-4) - 48 = 16 + 32 - 48 = 0\). Thus, both are solutions.
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.
Quadratic Formula
When you're dealing with a quadratic equation like the one given \(n^2 - 8n - 48 = 0\), a powerful tool is the quadratic formula. This formula helps you find the roots (solutions) of any quadratic equation and is expressed as:\[ n = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]Here is a breakdown of the elements:
- \(a\), \(b\), and \(c\) are coefficients from the quadratic equation in the standard form \(ax^2 + bx + c = 0\).
- The "\(\pm\)" symbol means you'll be finding two potential solutions.
Discriminant
The discriminant in a quadratic equation, represented by \(b^2 - 4ac\), helps determine the nature of the roots without having to solve the entire equation. It can reveal whether the equation has:
- Two distinct real roots
- One real double root
- Two complex roots
Roots of a Quadratic Equation
The roots of a quadratic equation are the values of \(x\) (or in our case, \(n\)) that make the equation true Here, after computing using the quadratic formula, we found:\[ n = \frac{-(-8) \pm \sqrt{256}}{2} \]which simplifies to:\[ n = \frac{8 \pm 16}{2} \]This gives us two roots:
- \(n = \frac{24}{2} = 12\)
- \(n = \frac{-8}{2} = -4\)