Halppppp

k  =  (6x + 12)(x - 8)

                                          Multiply out the right side of the equation.

k  =  6x² - 48x + 12x - 96

                                          Combine like terms.

k  =  6x² - 36x - 96

In an equation of the form   k  =  ax² + bx + c   with   a > 0,

the least possible value of   k   occurs at   $x\ =\ \text-\frac{b}{2a}$

So...

In an equation of the form   k  =  6x² - 36x - 96   with   6 > 0,

the least possible value of   k   occurs at   $x\ =\ \text-\frac{(\text-36)}{2(6)}\ =\ \frac{36}{12}\ =\ 3$

When  x = 3,     k   =   6(3)² - 36(3) - 96   =   6(9) - 36(3) - 96   =   54 - 108 - 96   =   -150

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