If using the method of completing the square to solve the quadratic equation x^2-20x+33=0x
2
−20x+33=0, which number would have to be added to "complete the square"?

Respuesta :

Answer:

The complete square of the given quadratic equation

( x - 10)² = 67

The solution of the quadratic equation

  x = 18.2     and x = 1.8

Step-by-step explanation:

Step(i):-

Given that the quadratic equation

         x² - 20 x +33 =0

         x² - 2(10) x +(10)²-(10)²+ 33 =0

By using (a-b)² = a² -2ab + b²

       ( x - 10)² -100 +33 =0

         ( x - 10)² - 67 =0

        ( x - 10)² = 67

Step(ii):-

The complete square   (x - 10)² = 67

                                     x -10  = ±√67

                                    x -10 = ± 8.1853

                      x -10 = 8.2   and x -10 = -8.2

                      x = 10+8.2   and x = 10 -8.2

                      x = 18.2     and x = 1.8