Find the difference of (7x³ + 2x² - 12) - (-2x³ - 4x)

(7x³ + 2x² - 12) - (-2x³ - 4x)

= 7x³ + 2x² - 12 + 2x³ + 4x {removed parentheses, distributing negative sign}

=

= 7x³ + 2x² - 12 + 2x³ + 4x {removed parentheses, distributing negative sign}

=

**9x³ + 2x² + 4x - 12**{combined like terms and wrote in decreasing order of the exponents}*- Algebra House*