Answer:
Step-by-step explanation:
12ab - 10b² - 18a² + 9ab + 12b² + 14a²
= 12ab + 9ab - 10b² + 12b² -18a² + 14a² {Combine like terms}
= (12 + 9)ab + (-10 + 12)b² + (-18 + 14)a²
= 21ab + 2b² - 4a²
ab + 2b² + 3b² - a² = ab + (2+3)b² - a²
= ab + 5b² - a²
Now find the difference
ab + 5b² - a² - [ 21ab + 2b² - 4a²]
= ab + 5b² -a² - 21ab - 2b² + 4a²
= ab - 21ab + 5b² - 2b² - a² + 4a²
= -20ab + 3b² + 3a²
2) 2x³ – 3x² y +2xy²+3y³ - unknown polynomial = x³ -2x² y+3xy²+4y³
2x³ – 3x² y +2xy²+3y³ = x³ -2x² y+3xy²+4y³ + unknown polynomial
2x³ – 3x² y +2xy²+3y³ - [ x³ -2x² y+3xy²+4y³] = unknown polynomial
2x³ – 3x² y +2xy²+3y³ - x³ + 2x² y- 3xy²- 4y³ =
2x³ - x³ -3x²y +2x²y + 2xy² - 3xy² + 3y³ - 4y³=
x³ - x²y - xy² - y³
Answer: x³ - x²y - xy² - y³
