Add: (3x² + 2x − 5) + (x² − 6x + 9)
- 4x² + 8x + 4
- 4x² − 4x + 4
- 3x⁴ − 4x + 4
- 4x² − 4x − 14
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B. 4x² − 4x + 4
Add like terms: 3x² + x² = 4x², 2x − 6x = −4x, and −5 + 9 = 4. Adding x² terms does not raise the exponent, so 3x⁴ is not correct.
Reference: Adding polynomials
Subtract: (5x² − 3x + 2) − (2x² + 4x − 6)
- 3x² + x − 4
- 3x² − 7x − 4
- 7x² + x − 4
- 3x² − 7x + 8
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D. 3x² − 7x + 8
Change the sign of every term in the second polynomial, then combine: 5x² − 2x² = 3x², −3x − 4x = −7x, 2 + 6 = 8. The answer 3x² + x − 4 subtracts only the first term and adds the rest.
Reference: Subtracting polynomials