1. 5x⁴ + 6x³ - 3x² - 4x² + 4 - 7
2. -7x³y + 4x³y + 4x²y² - 8x²y² - 2 + 1
3. 24y³ - 6y³ - 7y² + 7y² + 5 + 5
4. 2x⁵ - 11x⁵ - 6x³ - 12x² + 2x² + 8x - 4 + 6
5. 3y⁵ + 2y⁵ + y⁴ + 2y³ + 3y³ - 2y + 5 + 2 + 7
Arrange the polynomial and place those with the same terms together, then perform the indicated operation.