1. 7x - x - 3 + 8 = 6x + 5
2. (3a + 4) + (2a^2 + 5) - (9 - 7a) = 3a + 2a^2 - 7a + 4 + 5 - 9 = -2a^2
3. 3x^4 - 15x^2 - 5x^2 - 25 = 3x^4 - 15x^2 - 5x^2 - 25 = -17x^4 - 25
4. 10x^3y^2 - 5xy^2 = 5x^2 - 4y^2 = x^2y^2
(How did I get 4xy^2? 9x^2y^3 - 5x^2y = 4y^2)
5. -3x^3 (2x-4) = -6x^4 - 12x^3 = -18x^7
6. 4x^2 - 10x + 10x - 25 = 4x^2 - 25
7. 9x^2 + 27^2 - 30 + 15x^2 + 45x - 50 = 36x^4 - 30x = 6x^3 + 15x^2 = 21x^5 + 45x = 66x^6 - 50
8. 13m^7
9. (-3x + 5x -6) / (x - 2) = (2x - 6) / (x - 2) = x - 4
10. (3x^2 + 8) / (x - 6) = 2x + 2