X^(2) -22x=10\\ Solve by completing the square. Please show work, I'm really struggling to understand this.

Question

`x^(2) -22x=10\\`

Solve by completing the square. Please show work, I'm really struggling to understand this.

Answer 1

Explanation:

x^2 - 22x = 10

Next step is to complete the square on the left hand side of the equation and it would be balanced by adding the same number to the right side of the equation. It becomes

x^2 - 22x + (22/2)^2 = 10 + (22/2)^2

x^2 - 22x + (11)^2 = 10 + (11)^2

x^2 - 22x + (11)^2 = 10 + 121

x^2 - 22x + (11)^2 = 131

x^2 - 22x + 121^2 = 131

(x - 11)^2 = 131

Taking square root of both the left hand side and the right hand side of the equation, it becomes

x - 11 = ±√131

x - 11 = ±11.45

Adding 11 to the left hand side and the right hand side of the equation, it becomes

x - 11 + 11 = ±11.45 + 11

x = 11.45 + 11 or x = -11.45 + 11

x = 22.45 or x = - 0.45