Question

Adding which terms to 3x2y would result in a monomial? Check all that apply.
3xy
–12x2y
2x2y2
7xy2
–10x2
4x2y
3x3

Answer 1

Adding and subtracting a monomial requires having the same variables. No matter how big or small their coefficient is, if their variables do not match, they cannot be added or subtracted. The crucial part in adding or subtracting monomials is their sign. If the signs are the same, retain the sign. If the signs are different, subtract and keep the sign of the larger number.

3x2y + 3xy (cannot be added)
3x2y + (–12x2y) = -9x2y
3x2y + 2x2y2 (cannot be added)
3x2y + 7xy2 (cannot be added)
3x2y + (–10x2) (cannot be added)
3x2y + 4x2y = 7x2y
3x2y + 3x3 (cannot be added)