Question

What are the solutions of the standard form of quadratic equation x(x-8)=9?​

Answer 1

Answer:

x² -8x -9 = 0

hope it helps you : )

Answer 2

Answer:

The solutions of the quadratic equation x(x-8) = 9  are -1 and 9.

Step-by-step explanation:

Given quadratic equation is:

    x ( x - 8 ) = 9

⇒ $x^{2} -8x -9=0$

Here,

a = 1 , b = -8 , c = -9

Therefore , Solutions of the quadratic equation are:

$D = \sqrt{b^{2}-4ac}$

   = $\sqrt{(-8)^{2}-4*1*(-9) }$

   =  $\sqrt{64 + 36}$

   = 10

   $x_{1} = \frac{-b-D}{2a}$         and            $x_{2} =\frac{-b+D}{2a}$

  $x_{1} = \frac{-(-8)-10}{2(1)}$                       $x_{2} = \frac{-(-8)+10}{2(1)}$

 $x_{1} = \frac{8-10}{2}$                              $x_{1} = \frac{8+10}{2}$

 $x_{1} = \frac{-2}{2}$                                $x_{1} = \frac{18}{2}$

 $x_{1} = -1$                                $x_{2} = 9$