A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
Solve quadratic equation by completing the square. Check both roots.
problem below
anonymous
 3 years ago
Solve quadratic equation by completing the square. Check both roots. problem below

This Question is Closed

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

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

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

NotTim
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.0Those 2 values are then put into the brackets as you see them.

NotTim
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.0ok but there is supposed to be two answers

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

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

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

NotTim
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.0I did what the question asked. Solve quadratic equation by completing the square.

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

KingGeorge
 3 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
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.0ok george you are right now can you explain each step

KingGeorge
 3 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
 3 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
 3 years ago
Best ResponseYou've already chosen the best response.1Did this make sense?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0yes thank you but please view my next question
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.