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anonymous
 one year ago
Solve by completing the square
x^220x+30=0
anonymous
 one year ago
Solve by completing the square x^220x+30=0

This Question is Closed

KaiserTheSlayer
 one year ago
Best ResponseYou've already chosen the best response.0using this would help you and remember the a=1, b=20, and c=30

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[x^22*x*10+10^210^2+30=0\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what do you do after that? @surjithayer

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0do i used the quadratic formula to solve by completing squares? @KaiserTheSlayer

KaiserTheSlayer
 one year ago
Best ResponseYou've already chosen the best response.0so it would be x=18.36660026534076 and x= 1.63339973465925

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0Solving by square completion yields:\[x²20x=30\]\[x²20x + 100 = 70\]\[(x10)²=70\] There you have it. Do you the stepbystep?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[(x10)^2100+30=0\] \[\left( x10 \right)^2=70=\left( \sqrt{70} \right)^2\] \[x10=\pm \sqrt{70}\] x=?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0where is the 100 coming from?

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0You take half of the x coefficient, square it and add to both sides.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thats right! i sorta remember now

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0Don't forget to divide everything by whatever is multiplying the squared term ;). In this case, it's "1", so it won't matter.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so then to figure out what x is I solve... x10=\[\sqrt{70}\] and x10=\[\sqrt{70}\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0idk why it looks like that i was trying to write what you did on the last thing

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0Be careful! The second solution you gave is a COMPLEX number.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i know i have to do the whole i stuff for that cause its a negative square root

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0No, it's not:\[x10=\sqrt{70} \]or\[x10=\sqrt{70}\]

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0notice the minus sign is outside.

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0And that's it! you have your solutions! Just move the independent term to the other side.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yeah i got it now, thank you!

ChillOut
 one year ago
Best ResponseYou've already chosen the best response.0The whole thing about completing the square is to make the left side equation look like something like (xa)² or (x+a)²
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