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Answer:
7x+2x^2+3x^2+3+x=(7x+x)+(2x^2+3x^2)+3=8x+5x^2+3
Final answer: 8x+5x^2+3
Explanation:
Combining like terms is basically finding similar terms and doing the mathematic operation with them. In this case, the like terms are:
7x and x
2x^2 and 3x^2
3
Before every one of these numbers is a plus sign, so rearranging their order won't change the result.
If you have any questions, ask in the comments :>