Verified Answer :

  1. -x^2-8x-16
    2. 28x^2-33x+9
    3. 14x^2-9x-8
    4. 16x^2+48x+27
    5. 24x^2-24x-18
    6. 10x^2-31x-14
    7. -4x^2+12x-5
    8. -9x^2+64x+64
    9. 12x^2-42x+18
    10. 20x^2-24x-18
    11. 4x^2+10x+6
    12. 56x^2+34x-12
    13. 24x^+5x-14
    14. 8x^2-52x+72
    15. -18x^2-72x-64
    16. 12x^2+13x-4
    17. -8x^2-11x+10
    18. -24x^2-96x-72
    19. -40x^2+11x+2
    20. 16x^2+24x-16