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    Using the quadratic formula Zozosmithy

    Hi guys, Just wondering for the quadratic formula do we make the roots a minus or plus??? For example: When using brackets for -4squared, that equals to 16. Without using brackets for -4squared, that equals to -16. In simpler terms, (-4)squared=16 and -4squared=-16. Thanks.

    1. avatar image

      studyclix

      Hi Zozosmithy,

      If b = -4 then the b squared part would be (-4) squared which would be 16. Hope this helps.

    2. avatar image

      Zozosmithy

      Ok and what if b= +4?? Thanks.

    3. avatar image

      studyclix

      if b=4 then b squared would be +16 also.

      Any number squared will be a positive i.e. 3 squared = 9, (-3) squared = 9

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      hamzamughees

      if you have -4^2 (^ means to the power of) without brackets, the minus will not be squared, only the 4 will be squared and the minus sign will be added on to it later, e.g -4^2, the minus will be taken out, so 4^2 = 16, and then the minus will be added on, so -16. if you use the brackets, so (-4)^2, the minus will also be squared, - * - = + (* means multiply) 4 * 4 = 16, so the answer of (-4)^2 = +16, -4^2 = -16.

      hope this helped:)

    5. avatar image

      Dazzla16

      Hi Zozosmithy! As you know this is the quadratic formula:

      x=

      -b +/- sqrt(b^2 - 4ac)

      ________________

      2a

      when an equation is in the form: ax^2 + bx + c

      You will notice the coefficient of b^2 is positive. That means, no matter what integer you sub in for b, b^2 will be positive.

      Example: If b = -3, then b^2 = (-3)^2 = 9.

      In that case, you always have to put in the brackets.

    6. avatar image

      Dazzla16

      Hi Zozosmithy! As you know this is the quadratic formula:

      x=

      -b +/- sqrt(b^2 - 4ac)

      ________________

      2a

      when an equation is in the form: ax^2 + bx + c = 0

      You will notice the coefficient of b^2 is positive. That means, no matter what integer you sub in for b, b^2 will be positive.

      Example: If b = -3, then b^2 = (-3)^2 = 9.

      In that case, you always have to put in the brackets.

    7. avatar image

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