Answer:
5x^2 -3x +9
Explanation:
To subtract, line up the common terms. I add a 0 term to keep the terms in line.
5x^2 + 0x +7
- (0x^2 +3x- 2 )
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Distribute the negative sign.
5x^2 + 0x +7
- 0x^2 -3x + 2
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5x^2 -3x +9