a little help would be nice
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Answer:
13). -2x³ + x² + 1 14). x + 10y - 10z 15). -2x³ + x² + 1
Step-by-step explanation:
13). (x³ - x² + 4) - (3x³ - 2x² + 3)
= x³ - x² + 4 - 3x³ + 2x² - 3
= x³ - 3x³ - x² + 2x² - 3 + 4
= -2x³ + x² + 1
14). (3x + 4y - 3z) - (2x - 6y + 7z)
= 3x + 4y - 3z - 2x + 6y - 7z
= 3x - 2x + 4y + 6y - 3x - 7z
= x + 10y - 10z
15). (x³ - x² + 4) - (3x³ - 2x² + 3)
= x³ - x² + 4 - 3x³ + 2x² - 3
= x³ - 3x³ - x² + 2x² + 4 - 3
= -2x³ + x² + 1