Answer:
Step-by-step explanation:
6ab²+4a²b-3ab²+3a²b-2a²b²
= 4a²b+3a²b-3ab²+6ab²-2a²b² . . . commutative property of addition (twice)
= (4+3)a²b+(-3+6)ab²-2a²b² . . . . . . distributive property (twice)
= 7a²b+3ab²-2a²b²
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We have attempted to correct what we perceive to be typographical errors in the presentation of the problem. As written, you can't get to the second expression from the first, and the first expression doesn't match what you say you're trying to simplify.