/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 43 Solve each equation by factoring... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Solve each equation by factoring or the Quadratic Formula, as appropriate. $$ 2 x^{2}-50=0 $$

Short Answer

Expert verified
x = 5 and x = -5

Step by step solution

01

Move All Terms to One Side

Start by bringing all terms to one side of the equation to set the equation equal to zero. The given equation is \[ 2x^2 - 50 = 0 \]Add 50 to both sides to get:\[ 2x^2 = 50 \]
02

Simplify the Equation

Divide every term in the equation by 2 to make the coefficient of the quadratic term 1.\[ \frac{2x^2}{2} = \frac{50}{2} \]This simplifies to:\[ x^2 = 25 \]
03

Solve by Taking the Square Root

To solve for \( x \), take the square root of both sides of the equation.\[ \sqrt{x^2} = \sqrt{25} \]This gives:\[ x = 5 \] and \[ x = -5 \]
04

Verify the Solutions

Substitute \( x = 5 \) back into the original equation:\[ 2(5)^2 - 50 = 0 \]This simplifies to:\[ 50 - 50 = 0 \] which is true.Now, substitute \( x = -5 \):\[ 2(-5)^2 - 50 = 0 \]This simplifies to:\[ 50 - 50 = 0 \] which is also true.

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.

Factoring
Factoring is a technique used to solve quadratic equations by expressing the equation as a product of simpler expressions. It focuses on rewriting a quadratic equation into a form where it equals zero. The general form to start with is \( ax^2 + bx + c = 0 \). To factor, you look for two numbers that multiply to give \( ac \) (where \( a \) and \( c \) are the coefficients) and add up to \( b \) (the coefficient of \( x \)).

Once these two numbers are found, you can split the middle term \( bx \) into two terms, allowing you to group and factor by grouping. When it comes to our equation \( 2x^2 - 50 = 0 \), factoring isn’t used directly. However, if the equation were presented as \( x^2 - 25 = 0 \), we could apply the difference of squares method, recognizing it as \((x + 5)(x - 5) = 0\). Thus, giving the solutions \( x = 5 \) or \( x = -5 \).

Choosing the right approach depends on recognizing these kinds of patterns and expressions. Factoring can be highly effective but it requires identification of specific structures like perfect square trinomials or the difference of squares.
Quadratic Formula
The Quadratic Formula is a comprehensive solution for any quadratic equation \( ax^2 + bx + c = 0 \). When factoring seems difficult or impractical, using the Quadratic Formula serves as a reliable method to find solutions. The formula is given by:

\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]

This formula is derived from completing the square of the general form of a quadratic equation. The term inside the square root, \( b^2 - 4ac \), is known as the discriminant. The discriminant helps determine the nature of the roots:
  • If \( b^2 - 4ac > 0 \), there are two distinct real roots.
  • If \( b^2 - 4ac = 0 \), there is exactly one real root.
  • If \( b^2 - 4ac < 0 \), there are no real roots (roots are complex).
In the original equation \( 2x^2 - 50 = 0 \), substituting into the quadratic formula would work but isn't necessary because the equation simplifies easily after dividing by 2. Nevertheless, understanding this method is vital as it applies to more complex equations that do not factor easily.
Square Root Method
The Square Root Method is a straightforward technique for solving quadratic equations that have no linear term (where \( b = 0 \) in the standard form \( ax^2 + bx + c = 0 \)). It is especially useful when the equation can be rewritten in the form \( x^2 = k \), where solving it becomes a matter of taking the square root of both sides.

For example, the simplified equation \( x^2 = 25 \) in our problem can be effectively tackled using this method. By taking the square root of both sides, it gives \( x = \sqrt{25} \). As it's important to consider both positive and negative roots when dealing with square roots, the solutions are \( x = 5 \) and \( x = -5 \).

Here’s how you use the method step-by-step:
  • Step 1: Isolate the \( x^2 \) term if necessary (e.g., \( ax^2 = c \) becomes \( x^2 = \frac{c}{a} \)).
  • Step 2: Take the square root of both sides.
  • Step 3: Remember to write \( x = \pm \sqrt{x} \) to capture both solutions.
In our context, this method provided a quicker path to the solution after dividing the original equation \( 2x^2 = 50 \) by 2, simplifying the problem substantially.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

BUSINESS: MBA Salaries Starting salaries in the United States for new recipients of MBA (master of business administration) degrees have been rising approximately linearly, from \(\$ 78,040\) in 2005 to \(\$ 89,200\) in \(2010 .\) a. Use the two (year, salary) data points \((0,78.0)\) and \((5,89.2)\) to find the linear relationship \(y=m x+b\) between \(x=\) years since 2005 and \(y=\) salary in thousands of dollars. b. Use your formula to predict a new MBA's salary in 2020 . [Hint: Since \(x\) is years after 2005, what \(x\) -value corresponds to \(2020 ?]\)

89-90. Some organisms exhibit a density-dependent mortality from one generation to the next. Let \(R>1\) be the net reproductive rate (that is, the number of surviving offspring per parent), let \(x>0\) be the density of parents and \(y\) be the density of surviving offspring. The Beverton-Holt recruitment curve is $$ y=\frac{R x}{1+\left(\frac{R-1}{K}\right) x} $$ where \(K>0\) is the carrying capacity of the environment. Notice that if \(x=K\), then \(y=K\). Show that if \(x

BEHAVIORAL SCIENCES: Smoking and Educatior According to a study, the probability that a smoker will quit smoking increases with the smoker's educational level. The probability (expressed as a percent) that a smoker with \(x\) years of education will quit is approximately \(y=0.831 x^{2}-18.1 x+137.3\) (for \(10 \leq x \leq 16\) ). a. Graph this curve on the window \([10,16]\) by \([0,100]\). b. Find the probability that a high school graduate smoker \((x=12)\) will quit. c. Find the probability that a college graduate smoker \((x=16)\) will quit.

SOCIAL SCIENCE: Equal Pay for Equal Work Women's pay has often lagged behind men's, although Title VII of the Civil Rights Act requires equal pay for equal work. Based on data from \(2000-2008\), women's annual earnings as a percent of men's can be approximated by the formula \(y=0.51 x+77.2, \quad\) where \(x\) is the number of years since 2000 . (For example, \(x=10\) gives \(y=82.3\), so in 2010 women's wages were about \(82.3 \%\) of men's wages.) a. Graph this line on the window \([0,30]\) by \([0,100]\). b. Use this line to predict the percentage in the year 2020\. [Hint: Which \(x\) -value corresponds to 2020 ? Then use TRACE, EVALUATE, or TABLE.] c. Predict the percentage in the year 2025 .

$$ \begin{array}{l} \text { For each function, find and simplify }\\\ \frac{f(x+h)-f(x)}{h} . \quad(\text { Assume } h \neq 0 .) \end{array} $$ $$ f(x)=\frac{3}{x} $$

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.