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Okay sy mash members next on our little quadratic friendly

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exploration tour Here What is acts for the equation to

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x squared plus thirty six equals negative eighteen x So

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when we're solving a quadratic equation always start by setting

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one side of the equation over here and then we're

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going to put the zero thing he over here right

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So it might help to pretend that we're kali's hurting

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the terms to the left side like sheep And we're

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adding eighteen acts to both sides there See if we

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do that we get to x squared plus eighteen ax

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plus thirty six equal zero Okay Since each term of

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this quadratic is divisible by two well let's divide both

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sides of the equation by two to simplify the factoring

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process knows that the right side remains equal to zero

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since zero Divided by two in california is zero so

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we get x squared plus nine x plus eighteen Now

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we need two factors of the constant term eighteen that

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add up to the ex coefficient nine what are they

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Well what times What is eighteen Well could it be

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two and nine Yes but it's not one in eighteen

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Yes but it's not And yes it's three and six

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and conveniently three plus six is nine So it looks

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like that explosive six and then explodes three zero Well

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the final staff is set Each factor equals zero and

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salt for acts right So if x plus six zero

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than x cast to be a minus six And similarly

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three has to be minus three They're the solution given

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Equation is x equals negative six comma negative three and

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that's it The answer is b and don't get fooled

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by the others because they all use the wrong factors

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to get eighteen and other mistakes like that So answer

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is b but but

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