A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
solve the quadratic equation by comleting the square,
x^212x+7=0
anonymous
 3 years ago
solve the quadratic equation by comleting the square, x^212x+7=0

This Question is Closed

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Sum 29 on both sides and you get:\[x^212x+36=(x6)^2=29\]Do square root, isolate x and you get your answer.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Where did you get 29 from?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0(a+b)^2=a^2+2ab+b^2 To complete the squares is to go from something like the right part to something on the left side. a in this case is clearly x, and because of the second term, we know that b is 6, but we only have 7 on the place of b² and we need to have 36. What is missing for we to get 36 is what we need to add, wich is 29.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0k i know im late on this but ill explain it anyway... \[x^212x+7=0\]we're gonna complete the square for this first move the \(7\) over to the other side:\[x^212x=7\]now fill in the following blanks with the square of half the middle term [\(({12\over2})^2\)]:\[x^212x+\text{___}=7+\text{___}\]\[x^212x+36=7+36\]now combine like terms:\[x^212x+36=29\]next write the simplified version of \(x^212x+36\) which is \((x6)(x6)\)=\((x6)^2\):\[(x6)^2=29\]square root both sides:\[x6=\sqrt{29}\]add 6 to both sides:\[\large x=6\pm\sqrt{29}\] hope you get how to do this now! :) ...sorry it was so late
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.