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anonymous
 4 years ago
Solve quadratic equation by completing the square. Check both roots.
problem below
anonymous
 4 years ago
Solve quadratic equation by completing the square. Check both roots. problem below

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anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0please explain each step I am having trouble with it

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.02(x^26x+8)=0 2[(x4)(x2)]=0

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0please do explain why you do each step

NotTim
 4 years ago
Best ResponseYou've already chosen the best response.01st step Factor out 2. Second step What 2 numbers add to the end value, and multiply to the middle value?

NotTim
 4 years ago
Best ResponseYou've already chosen the best response.0Those 2 values are then put into the brackets as you see them.

NotTim
 4 years ago
Best ResponseYou've already chosen the best response.0And here, the signs of positive and negatives are reversed because when you solve for x individually, x4=0 x=4. Ok?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ok but there is supposed to be two answers

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1339466532153:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1339466562615:dw

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0dw:1339466604939:dw

NotTim
 4 years ago
Best ResponseYou've already chosen the best response.0eh, you might be might be making this more difficult than it actually is

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0I did what the question asked. Solve quadratic equation by completing the square.

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1You made a small mistake. The 8 should also be multiplied by 2.

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1Leaving you with\[2(x^26x+99+8)=2((x3)^21)=2(x3)^22\]

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1Set equal to 0, and get \[2(x3)^22=0\implies(x3)^2=1\]Take the root, and solve. \[x3=\pm1\implies x=4\quad\text{or}\quad x=2\]

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0ok george you are right now can you explain each step

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1The hardest part is the first couple steps. You start with \[2x^212x+16=2(x^26x+8)\]The next part is where you complete the square. You take half of \(6\), square it, and then add/subtract it. So you get\[2(x^26x+8)=2(x^26x+\left(\frac{6}{2}\right)^2\left(\frac{6}{2}\right)^2+8=2(x^26x+99+8)\]

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1Now you simplify as I described before. It's important that you simplify \[x^26x+99+8\]as \((x3)^21\). That's the whole point of completing the square. You add/subtract just the right amount so you can have the square of a binomial. From there, you can solve for that square easily, and then just take a square root.

KingGeorge
 4 years ago
Best ResponseYou've already chosen the best response.1Did this make sense?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0yes thank you but please view my next question
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