adding and subtracting polynomials

Find the sum.
(2x² + 5x - 7) + ( 3 - 4x² + 6x)

• 2x² + 3x +1
• -2x² - 11x -4
• 2x² + 5x -7
• -2x² + 11x -4

Simplify:

• 9n³ + 4n
• 7n³ + 6
• -3n³ + 2
• 7n⁶ + 6

Add the polynomials.
(2x + 5y) + (3x - 2y)

• 3x + 5y
• 5x + 3y
• 5x + 7y
• 7xy + 1xy

Find the difference. 
(3- 2x + 2x²) - (4x -5 +3x²)

• x_² + 6x + 8
• 2x² + 5x - 7
• -x² -6x + 8
• -2x² + 11x - 4

Simplify each expression.
(6b³ + 6 - b⁴) - (8b³ - 6b⁴ + 2)

• 4b⁴ - 2b³ + 7
• 5b⁴ - 2b³ + 4
• b⁴ - 2b³ + 7
• 5b⁴ - 2b³ + 7

Add the polynomials.
(2x + 5y) + (3x - 2y)

• 3x + 5y
• 5x + 3y
• 5x + 7y
• 7xy + 1xy

Add: (3x - 2) + (3x² + 6x)

• 3x² + 9x - 2
• 6x² + 4x
• 3x² + 3x - 2
• 6x² + 6x - 2

Add or Subtract to Simplify:
(x⁵ + x³) - (6x - x³ + 6x⁵)

• -5x⁵ + 2x³ - 6x
• 7x⁵ - 6x
• -5x³ + 2x² - 6x
• -5x⁵ - 6x

Simplify each expression.
(4n⁴ - 8n + 4) - (8n² + 4n⁴ + 1)

• -8n² - 8n + 3 
• -7n² - 8n + 3 
• -6n² - 8n + 3
• -7n² - 4n + 3

Combine like terms to simplify:
 (5x + 2) + (4x + 5)

• 9x -7
• -9x-11
• 9x+7
• x+7