ricky2007 ricky2007 24-01-2020 Mathematics contestada PracticeSimplify each expression by combining like terms.1. 6x + 4x2. – 5y + 2y 3. – 3m - 8(m + 1)4. -81r - 2) + 6(r - 2) -5. 9m - 7m + 13