Find the value of a for which 2x^3 - ax^2 - 12x -7 has a repeated factor

2x3-ax2-12x-7
repeated-factor

#1

Find the value of a for which 2x^3 - ax^2 - 12x -7 has a repeated factor. So sorry this is very urgent as I have an Advanced Mah test tmw and I am very lost. Thanks so much!

Answer:

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