273,094 views
32 votes
32 votes
Solve the equation by completing the square. show all solutionsx^2 - 12x + 11 = 0

User HobbitOfShire
by
2.9k points

1 Answer

12 votes
12 votes

x²- 12x + 11 = 0

subtract 11 from both-side

x² - 12x = -11

Add square of half of the coefficient of x to both-side

x² - 12x + (-6)² = -11 + (-6)²

(x- 6)² = -11 + 36

(x-6)² =25

Take the square root of both-side

x - 6 = ±5

add 6 to both-side

x = ±5 + 6

Either x = 5 + 6 or x = -5+6

x = 11 or x = 1

User Bythescruff
by
2.3k points