`1. = x^2+2x`
`2. = x^2-7x`
`3. = 2x^2+8x`
`4. = -x^2-5x`
`5. = 28x+8x^2`
`6. = 5x^2+5x`
`7. = -8x^2+2x`
`8. = 2x^3+x^2`
`9. = -3x^3+6x^4`
`10. = 8x^2+6x^2-2x`
`11. = 2x^3-6x^2-4x`
`12. = 2x^3-3x`
`13. = 8x^3-12x+2x`
`14. = 15xy-12xy^2`
`15. = 2x^3y^2-8x^2y+10xy^2`
`16. = -10x^3y^2+15x^3y^3-5x^2y`
`17. = 4x^2+8x`
`18. = 10x^3-5x^2+5x`
`19. = 2x^3-6x^2+10x`
`20. = 2x^2-xy`
`21. = 6x^2y^2-3xy^4`
`22. = -2x^3+10x^2-8x`
`23. = -x^3y-xy`
`24. = -2x^3y^2+1/6x^2y^2-4xy^2`
`25. = 12x^3-12x^2+8x`
`26. = -2x^2+7x`
`27. = 6x^4y-10x^3y^2+8x^2y^3`
`28. = -1/2x^4+x^3-2x^2`
`29. = -8x+12x^3`
`30. = 4x^3y-8x^2y^2+12xy^3`
