Algebra Quadratic Equations

What are the pros and cons of completing the square as a way to solve quadradic equations?

  1. 👍 0
  2. 👎 0
  3. 👁 1,030
  1. Completing the square is not the easiest way to solve quadratic equations; its strength lies in the fact that the process is repetitive and predictable.

    Here is the best news: completing the square ALWAYS (SAY ALWAYS) will work, unlike the factoring method, which of course, requires that the trinomial be factorable.

    1. 👍 0
    2. 👎 0
  2. I find the quadratic equation
    x = [-b +/- sqrt(b^2-4ac)]/2a
    the easiest to use, unless a way of factoring is obvious. It is derived by completing the square, after all. It tells you the number of real roots right away (from the value of b^2 - 4ac). The hard part is memorizing it, but after a while it becomes routine.

    1. 👍 1
    2. 👎 0
  3. I use the following rule:
    If the coefficient of the squared term is 1 and the coefficient of the first degree term is even, then I would use completing the square, otherwise just use the quadratic formula

    e.g.

    x^2 - 12x -5 = 0
    x^2 - 12x = 5
    x^2 - 12x + 36 = -5 + 36
    (x-6)^2 = 31

    x = 6 ± √31

    In this case this method is actually faster and easier than using the formula, since the formula answer has to be broken down to lowest terms.

    1. 👍 0
    2. 👎 1
  4. Thank you.

    1. 👍 0
    2. 👎 0
  5. Cool rule, thank you.

    1. 👍 0
    2. 👎 0
  6. Thank you for the example.

    1. 👍 0
    2. 👎 0

Respond to this Question

First Name

Your Response

Similar Questions

  1. Algebra Question

    Quadratic equations can be solved by graphing, using the quadrat completing the square, and factoring. What are the pros and cons these methods? When might each method be most appropriate?

  2. criminal justice

    What are the pros and cons or arguments for and against the just desert punishment theory?

  3. Algebra

    Which of the following statements is true? A. Any quadratic equation can be solved by completing the square. B. Completing the square always gives two distinct solutions. C. You can’t complete the square if there is no constant

  4. Ethics - Christian-based

    What are the pros and cons of using your conscience?

  1. ALGEBRA--MAT 117

    Quadratic equations can be solved by graphing, using the quadratic formula, completing the square, and factoring. What are the pros and cons of each of these methods? When might each method be most appropriate? Which method do you

  2. Math

    what are the pros and cons of the substitution method in a system of equations?

  3. maths

    Consider the equation x(square) + 4px + 2q = 0 where p and q are real constants. a) by completing square, show that (x+2p)square =4P(SQUARE)-2q b) Hence show that x= -2p +/- square root(4 p(square) -2p ) c) Use the above results

  4. Algebra

    I was given this answers to a problems I solved but I do not understand what she means hope you can help. Before attempting to solve this quadratic equation, determine how many solutions there will be for this quadratic equation.

  1. social studies 9

    Pros and cons of the Quebec Act

  2. world history

    what are the pros and cons to fur trades in canada in 1600?

  3. social studies

    What are the pros and cons of textbook social studies learning?

  4. algebra

    "Systems of equations can be solved by graphing or by using substitution or elimination. What are the pros and cons of each method? Which method do you like the best? Why? What circumstances would cause you to use a different

You can view more similar questions or ask a new question.