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is there a easier way to learnt Quadratic Equations?

i do not understand this topic and i need help


Could you give a little more information about what you want to know about quadratic equations?  For example, finding the zeros of the equation, graphing, etc.

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Kerrie T. | math and science from a professional academic scientistmath and science from a professional aca...
4.8 4.8 (332 lesson ratings) (332)

I think you should play angry birds! No really, we do it in math class all the time.  A quadratic equation describes a parabola, which just happens to be the shape of the curve made by the bird as it is sling-shotted through the air.  Well, really it is an inverted parabola, and I will get to that in a minute.

Here are quadratics in a nutshell:

  1. The standard equation lists the terms in descending order with highest power first.  Ax2 + Bx + C.  
    • This form is not particularly useful, except that the sign of A will tell you whether the curve is right side up (concave up) or upside down (think "angry bird in flight") (concave down).  If A > 0 the parabola is right side up....
    • Oh, and the constant C gives you the y- intercept, just like the constant does in the equation for a line
  2. The intercept form of the equation A(x-p)(x-q).  This is the "factored" form of the equation, and reveals the only reason why any self respecting angry birds fan would ever want to factor a quadratic in the first place.  Because they want to find the x-intercepts, or in other words, where the angry bird will land!
    • Since The "solution", "root" or "zero" of this equation is given by setting the whole thing to zero, we can use the zero multiplicity rule (ZMP) to find out where the function crosses the x axis.  The ZMP just says that when you multiply three unknown numbers and you know the product is zero, that one or more of the unknowns must be equal to zero.  So either
      • A=0 (boring)
      • (x-p) = 0 (possibly where the angry bird left the sling shot)
      • (x-q) = 0 (where the angry bird will land.  Hopefully on those annoying pigs!)
  3. Lastly, there is the vertex form of the equation (x-h)2 +k.  Once again, why would any serious sling-shotter be interested in this algebraic form of torture?  Well, this equation is useful for telling us the  highest point in flight (h,k) of the parabolic bird in question.  Putting the equation into this form is far more tortuous than the other bits of algebraic manipulation, and is called "completing the square".  In this short, angry treatise, it is beyond the scope of my sense of humor.  But fear not, there are internet resources which abound...if you are really interested, you can respond to my answer and I will continue....

Happy sling-shotting!