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3 votes
Solve x2+4x-7=0 by completing the square

User Hasayakey
by
5.9k points

2 Answers

3 votes
(X+2)^2 - 2 - 7
(X+2+3) (x+2-3)
User Thierry Prost
by
5.0k points
5 votes

Answer:

-2- √11

-2+√11

Explanation:

  • x²+4x-7=0
  • x²+4x+4- 11=0
  • (x+2)²-11=0
  • (x+2+√11)(x+2-√11)=0
  • x+2+√11=0 ⇒ x= -2- √11
  • x+2 -√11=0 ⇒ x= -2+√11
User GraphicalDot
by
4.9k points