What's the difference between this polynomials (9x² + 8x) - (2x² + 3x) ?

Remove the parentheses and combine the like terms. Like terms have same variable / same exponent.

(9x² + 8x) - (2x² + 3x)

= 9x² + 8x - 2x² - 3x {removed parentheses, distributing negative sign through second set of parentheses}

(9x² + 8x) - (2x² + 3x)

= 9x² + 8x - 2x² - 3x {removed parentheses, distributing negative sign through second set of parentheses}

**= 7x² + 5x**{combined like terms}__Ask the House__