Question 42106
First line up the polynomials.  Be sure to place all like-terms underneath each other:
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+3+5k^2-2k
-10+2k^2-3k
____________

.
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Add the like-terms:
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+3+5k^2-2k
-10+2k^2-3k
____________
-7 + 7k^2-5k
.
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Arrange in descending order of degrees:
 7k^2-5k-7