1) (2n-3n)(5m+n) - 10(m+n)²= (-n)(5m+n) - 10(m+n)²= -5mn - n² - 10(m² + 2mn + n²)= -5mn - n² - 10m² - 20mn - 10n²= -5mn - 20mn - 10m² - n² - 10n²= -25mn - 10m² - 11n²
2) (2√x-√y)² + 4√xy= (2√x - √y)(2√x - √y) + 4√xy= 4x - 4√xy - 4√xy + y + 4√xy= 4x + y + 4√xy
1) (2n-3n)(5m+n) - 10(m+n)²
= (-n)(5m+n) - 10(m+n)²
= -5mn - n² - 10(m² + 2mn + n²)
= -5mn - n² - 10m² - 20mn - 10n²
= -5mn - 20mn - 10m² - n² - 10n²
= -25mn - 10m² - 11n²
2) (2√x-√y)² + 4√xy
= (2√x - √y)(2√x - √y) + 4√xy
= 4x - 4√xy - 4√xy + y + 4√xy
= 4x + y + 4√xy