Add ; `7x^2-4x+5,\ -3x^2+2x-1\ a n d\ 5x^2-x+9.`

Add 7x^(2)-4x+5,-3x^(2)+2x-1 and 5x^(2)-x+9

Add : 5x^(2) , - 9x^(2)

Add: 7x, -3x, 5x, -x, -2x

Add 7x^(2) -8x + 5, 3x^(2) -8x +5 and -6x^(2) + 15x - 5

Add: (i) x y^2+4x^2y-7x^2y-3x y^2+3\ a n d\ x^(2y)+x y^2 (ii) 5x^2+7y-6z^2,\ 4y+3x^2,9x^2+2z^2-9y\ a n d\ 2y-2x^2

Add: (i) x y^2+4x^2y-7x^2y-3x y^2+3\ a n d\ x^2y+x y^2 (ii) 5x^2+7y-6z^2,\ 4y+3x^2,9x^2+2z^2-9y\ a n d\ 2y-2x^2

Add: 5x^(2) - 7x + 3, -8x^(2) + 2x -5 and 7x^(2) - x - 2

Add : 5x^2-1/3x+5/2,-1/2x^2+1/2x-1/3a n d-2x^2+1/5x-1/6dot

Add the following expressions: (i) 8a-6a b+5b ,\ -6a-a b-8b\ a n d-4a+2a b+3b (ii) 5x^3+7+6x-5x^2,\ 2x^2-8-9x ,\ 4x-2x^2+3x^3,\ 3x^3-9x-x^2\ a n d\ x-x^2-x^3-4