We were recently reviewing quadratic equations in my algebra 1 class. As my teacher simplified equation after equation on the board, I began to get this nagging feeling there was something incorrect.(adsbygoogle = window.adsbygoogle || []).push({});

I have pin pointed where I believe an error was made.

At this point in solving a quadratic equation, (6 +/- 2 root24)/2, my teacher simply cancels out the 6andthe 2 at once. I disagree here. It is a rule that you cannot cancel each component of an equation where a term is seperated by a + or - sign (of course, one can cancel the two since it is being multiplied with the "root24"). Instead, it I believe one must factor out a 2 from the numerator, then cancel out the 2 in the denominator.

my way:

1.)

6 +/- 2 root24 2(3 +/- root24)

-------------- = ---------------- = 3 +/- root24

2 2

2.)

The way my teacher does it:

6 +/- 2 root24 6/2 +/- 2/2 root24 = 3 +/- root24

--------------=

2

I realize that essentially, when you factor (as I did) , you are dividing each term, seperately by 2. However on the second example, one is dividing each term by the exact same integer.

is my analysis correct or incorrect?

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# Quadratic dillema

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