Look below for problem
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Answer:
Step-by-step explanation:
(3x^2 + 2x) + (-x + 9) Remove the brackets
3x^2 + 2x - x + 9 Watch out for the sign in front of the x
3x^2 + x + 9 No more reduction can take place.
(-2x^2 + 5x - 7) + (3x + 7) Remove the brackets
-2x^2 + 5x - 7 + 3x + 7
-2x^2 + 5x + 3x - 7 + 7 Combine
-2x^2 + 8x The 7s cancel -- they are of opposite signs.
No more reduction can take place. The powers on the variables have to be equal before any cancelation can take place.