Expanding the left side of the equation, we get:
x^3 - 6x^2 + 9x + 3x^2 - 18x + 27 = 7x - 21
Now simplify the equation:
x^3 - 6x^2 + 9x + 3x^2 - 18x + 27 = 7x - 21x^3 - 3x^2 - 9x + 27 = 7x - 21x^3 - 3x^2 - 9x - 7x + 27 + 21 = 0x^3 - 3x^2 - 16x + 48 = 0
So, the simplified equation is x^3 - 3x^2 - 16x + 48 = 0.
Expanding the left side of the equation, we get:
x^3 - 6x^2 + 9x + 3x^2 - 18x + 27 = 7x - 21
Now simplify the equation:
x^3 - 6x^2 + 9x + 3x^2 - 18x + 27 = 7x - 21
x^3 - 3x^2 - 9x + 27 = 7x - 21
x^3 - 3x^2 - 9x - 7x + 27 + 21 = 0
x^3 - 3x^2 - 16x + 48 = 0
So, the simplified equation is x^3 - 3x^2 - 16x + 48 = 0.