Question 39091
Just combine like terms.  So... 
{{{ (9+4x+8^2+2x^3)+(9-4x+8x^2-2x^3)=8x^2+18 }}}
To divide, just put them over each other like....
{{{ 14x^4/7x -56x^3/7x+49x/7x = 2x^3-8x^2+7 }}}
For multiplying, use the FOIL method (First numbers, Outside numbers, Inside numbers, and Last numbers).
{{{ (7x-4)(x-6) = 7x^2+42x-4x+24 = 7x^2+38x+24 }}}
Again, combine like terms for subtracting and adding... However, change the subtraction sign to addition and all the numbers after it to their opposite.
{{{ (3x^4+5x^3-8)-(3x^2-6x+3) = (3x^4+5x^3-8)+(-3x^2+6x-3) = 3x^4+5x^3-3x^2+6x-11 }}}
Good Luck and I hope this helped.
-Canti