Answer:
qn 10. 15mn² - 23m²n +4m³
Explanation:
1. distribute 4m through the parenthesis
8mn² - 12m²n + 4m³ - 2n(5m² - 3nm) + nm(n-m)
2. use the commutative property to reorder the terms
8mn² - 12m²n + 4m³ - 2n(5m² - 3mn) + mn(n - m)
3. distribute -2n through the remaining parenthesis
8mn² - 12m²n + 4m³ -10m²n + 6mn² + mn² - m²n
4. collect like terms
8mn² + 6mn² + mn² - 12m²n - 10m²n - m²n + 4m³
5. complete bodmas
15mn² - 23m²n +4m³
that's is how you do it so the answer is
15mn² -23m²n + 4m³