Question

Solve the equation by completing the square round to the nearest hundredth if necessary x^2 - 2x = 24

Answer 1

To complete the square:
1) Move the "non-x" term to the right.
It's already there.

2) Divide the equation by the coefficient of x^2.
It's already done.  Coefficient of x^2 is 1.

3)  • take the coefficient of X
this is -2

      • divide it by 2
-2 / 2 =-1

      • square that number
-1^2 = 1

      • then add it to both sides of the equation.
x^2 -2x = 24
x^2 -2x +1 = 25

4) take the square root of both sides of the equation (remember that each square root has TWO solutions).

Taking the square root of
x^2 -2x +1 = 25

equals
(x -1) = 5 AND

(x -1) = -5

So, x = 6 and
x = -4

Source:
http://www.1728.org/quadr2.htm
(See first half of page).