Evaluate
9k^{2}+21k-9
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9k^{2}+21k-9
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7k^{2}+9k-8+2k^{2}+12k-1
To find the opposite of -2k^{2}-12k+1, find the opposite of each term.
9k^{2}+9k-8+12k-1
Combine 7k^{2} and 2k^{2} to get 9k^{2}.
9k^{2}+21k-8-1
Combine 9k and 12k to get 21k.
9k^{2}+21k-9
Subtract 1 from -8 to get -9.
7k^{2}+9k-8+2k^{2}+12k-1
To find the opposite of -2k^{2}-12k+1, find the opposite of each term.
9k^{2}+9k-8+12k-1
Combine 7k^{2} and 2k^{2} to get 9k^{2}.
9k^{2}+21k-8-1
Combine 9k and 12k to get 21k.
9k^{2}+21k-9
Subtract 1 from -8 to get -9.
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