Question

factorisation of z²-6z+9​

Answer 1

-z2 - 6z - 9 = -1• (z2 + 6z + 9) =

z = -3

Answer 2

Answer:

    - B  ±  √ B2-4AC

  z =   ————————

                      2A

  In our case,  A   =     1

                      B   =    -6

                      C   =   9

Accordingly,  B2  -  4AC   =

                     36 - 36 =

                     0

Applying the quadratic formula :

               6 ± √ 0

   z  =    ————

                   2

The square root of zero is zero

This quadratic equation has one solution only. That's because adding zero is the same as subtracting zero.

The solution is:

  z = 6 / 2 = 3

One solution was found :

 z = 3

HOPE IT HELPS YOU!!

HAVE A GREAT DAY!!