Question

explain me completing square method

Answer 1

Consider the quadratic equation x²  + 4x - 23 = 0
Step 1: Make the coefficient of x² 1 ( Here in the equation coefficient of x² is 1 )
Step 2 : Shift the constant term to right side
               x²  + 4x = 23
Step 3: Take half of coefficient of x 
             4/2 = 2
Step 4: Square the coefficient of x and add it on both sides
               2² =4
                 x²  + 4x +2² = 23 +2
           ⇒  (x + 2)² = 25
Step 5 : Now simplify the equation to get the value of x
               x+2  = √25
               x+2  = +_5
               x  = 5 - 2 or  -5 - 2
               x  = 3 or x  = -7