How do you solve using the completing the square method 2x2+6x−5=0?

1 Answer
Jim G.
Apr 15, 2018

x=−32±12√19

Explanation:

using the method of completing the square

∙ the coefficient of the x2 term must be 1

factor out 2

⇒2(x2+3x−52)=0

∙ add/subtract (12coefficient of the x-term)2 to
x2+3x

⇒2(x2+2(32)x+94−94−52)=0

⇒2(x+32)2+2(−94−52)=0

⇒2(x+32)2−192=0

⇒2(x+32)2=192

⇒(x+32)2=194

take the square root of both sides

√(x+32)2=±√194←note plus or minus

⇒x+32=±12√19

⇒x=−32±12√19←exact solutions

Related questions
See all questions in Completing the Square
Impact of this question
5622 views around the world
You can reuse this answer
Creative Commons License