Solve For { X $}$ In The Equation:$ X^2 + 20x = -20 }$The Solutions Provided Are ${ X = 10 \pm \sqrt{80 }$ { X = 4\sqrt{5} \pm 10 \} $[ \begin{align*} x &= -10 + \sqrt{80} \ x &= -10 \pm

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Introduction

Solving quadratic equations is a fundamental concept in mathematics, and it is essential to understand the different methods and techniques used to find the solutions. In this article, we will focus on solving the equation x2+20x=−20x^2 + 20x = -20 and explore the different solutions provided.

The Equation

The given equation is x2+20x=−20x^2 + 20x = -20. To solve for xx, we need to isolate the variable xx on one side of the equation. We can start by adding 2020 to both sides of the equation to get:

x2+20x+20=0x^2 + 20x + 20 = 0

Completing the Square

One of the methods used to solve quadratic equations is completing the square. This method involves rewriting the quadratic equation in a perfect square form, which makes it easier to find the solutions. To complete the square, we need to add and subtract (20/2)2=100(20/2)^2 = 100 to the left-hand side of the equation:

x2+20x+100−100+20=0x^2 + 20x + 100 - 100 + 20 = 0

Simplifying the Equation

Now, we can simplify the equation by combining like terms:

(x+10)2−100+20=0(x + 10)^2 - 100 + 20 = 0

Rearranging the Equation

Next, we can rearrange the equation to get:

(x+10)2=80(x + 10)^2 = 80

Taking the Square Root

To find the solutions, we need to take the square root of both sides of the equation. Since we are dealing with a quadratic equation, we need to consider both the positive and negative square roots:

x+10=±80x + 10 = \pm \sqrt{80}

Simplifying the Square Root

We can simplify the square root by factoring out the perfect square:

x+10=±16×5x + 10 = \pm \sqrt{16 \times 5}

Simplifying Further

Now, we can simplify further by taking the square root of the perfect square:

x+10=±45x + 10 = \pm 4\sqrt{5}

Solving for xx

Finally, we can solve for xx by subtracting 1010 from both sides of the equation:

x=−10±45x = -10 \pm 4\sqrt{5}

Alternative Solutions

The solutions provided are:

x=10±80x = 10 \pm \sqrt{80}

x=45±10x = 4\sqrt{5} \pm 10

Discussion

In this article, we have solved the equation x2+20x=−20x^2 + 20x = -20 using the method of completing the square. We have also explored the different solutions provided and discussed the alternative solutions. The solutions provided are:

x=−10+80x = -10 + \sqrt{80}

x=−10±45x = -10 \pm 4\sqrt{5}

Conclusion

Solving quadratic equations is a fundamental concept in mathematics, and it is essential to understand the different methods and techniques used to find the solutions. In this article, we have focused on solving the equation x2+20x=−20x^2 + 20x = -20 and explored the different solutions provided. We have also discussed the alternative solutions and provided a step-by-step guide on how to solve the equation.

Frequently Asked Questions

  • Q: What is the method of completing the square? A: The method of completing the square involves rewriting the quadratic equation in a perfect square form, which makes it easier to find the solutions.
  • Q: How do I simplify the square root? A: You can simplify the square root by factoring out the perfect square and then taking the square root of the perfect square.
  • Q: What are the alternative solutions? A: The alternative solutions are x=10±80x = 10 \pm \sqrt{80} and x=45±10x = 4\sqrt{5} \pm 10.

Final Thoughts

Solving quadratic equations is a fundamental concept in mathematics, and it is essential to understand the different methods and techniques used to find the solutions. In this article, we have focused on solving the equation x2+20x=−20x^2 + 20x = -20 and explored the different solutions provided. We have also discussed the alternative solutions and provided a step-by-step guide on how to solve the equation.

Q&A: Solving Quadratic Equations

Q: What is a quadratic equation?

A: A quadratic equation is a polynomial equation of degree two, which means the highest power of the variable is two. It is typically written in the form ax2+bx+c=0ax^2 + bx + c = 0, where aa, bb, and cc are constants.

Q: What is the method of completing the square?

A: The method of completing the square involves rewriting the quadratic equation in a perfect square form, which makes it easier to find the solutions. This is done by adding and subtracting a constant term to the left-hand side of the equation.

Q: How do I simplify the square root?

A: You can simplify the square root by factoring out the perfect square and then taking the square root of the perfect square. For example, 16×5=16×5=45\sqrt{16 \times 5} = \sqrt{16} \times \sqrt{5} = 4\sqrt{5}.

Q: What are the alternative solutions?

A: The alternative solutions are x=10±80x = 10 \pm \sqrt{80} and x=45±10x = 4\sqrt{5} \pm 10. These solutions can be obtained by rearranging the equation and taking the square root of both sides.

Q: How do I solve for xx?

A: To solve for xx, you need to isolate the variable xx on one side of the equation. This can be done by adding or subtracting a constant term to both sides of the equation.

Q: What is the final solution?

A: The final solution is x=−10±45x = -10 \pm 4\sqrt{5}. This solution can be obtained by subtracting 1010 from both sides of the equation.

Q: What are some common mistakes to avoid when solving quadratic equations?

A: Some common mistakes to avoid when solving quadratic equations include:

  • Not adding or subtracting the correct constant term to both sides of the equation
  • Not simplifying the square root correctly
  • Not isolating the variable xx on one side of the equation

Q: How do I check my solution?

A: To check your solution, you can substitute the value of xx back into the original equation and verify that it is true. If the equation is true, then your solution is correct.

Q: What are some real-world applications of quadratic equations?

A: Quadratic equations have many real-world applications, including:

  • Modeling the trajectory of a projectile
  • Finding the maximum or minimum value of a function
  • Solving problems involving optimization

Q: How do I use technology to solve quadratic equations?

A: There are many online tools and software programs that can be used to solve quadratic equations, including:

  • Graphing calculators
  • Online equation solvers
  • Computer algebra systems

Q: What are some tips for solving quadratic equations?

A: Some tips for solving quadratic equations include:

  • Always read the problem carefully and understand what is being asked
  • Use the correct method for solving the equation
  • Check your solution carefully to ensure that it is correct

Conclusion

Solving quadratic equations is a fundamental concept in mathematics, and it is essential to understand the different methods and techniques used to find the solutions. In this article, we have focused on solving the equation x2+20x=−20x^2 + 20x = -20 and explored the different solutions provided. We have also discussed the alternative solutions and provided a step-by-step guide on how to solve the equation. Additionally, we have answered some common questions and provided tips for solving quadratic equations.