Answer:
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Explanation:
x(2x+4)+7(2x+4)[3x-6]=0
(2x^2 + 4x + 14x + 28)(3x-6)=0
(2x^2 + 18x + 28)(3x-6)=0
3x(2x^2 + 18x + 28) -6(2x^2 +18x + 28)=0
6x^2 + 54x^2 + 84x - 12x^2 - 108x - 168 =0
6x^2 + 54x^2 - 12x^2 + 84x - 108x - 168 =0
48x^2 - 24x - 168 =0 {quadratic equation}