(9x^2y^4)^3 = 729x^6y^12

Let's solve this problem by representing the three consecutive even numbers as x, x + 2, and x + 4.

According to the given information, the sum of these numbers is 270:

x + (x + 2) + (x + 4) = 270

Combining like terms, we have:

3x + 6 = 270

Subtracting 6 from both sides:

3x = 264

Dividing both sides by 3:

x = 88

Therefore, the three consecutive even numbers are 88, 90, and 92.

(-3x^2 + 9x^4 - 8 - 5x^3) - (-4 - 3x^3 + 4x^4 + 8x^2)
= -3x^2 + 9x^4 - 8 - 5x^3 + 4 + 3x^3 - 4x^4 - 8x^2
= 5x^4 - 2x^3 - 11x^2 - 4

To simplify the given polynomial, combine like terms:

cd^2 + 6a^2c^2 - 8cd^2 + a^2c^2

Combine the terms with the same variables:

(cd^2 - 8cd^2) + (6a^2c^2 + a^2c^2)

Combine the coefficients:

-7cd^2 + 7a^2c^2

So, the simplified polynomial is -7cd^2 + 7a^2c^2.