Solve for k
k=4
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7k-21=3k-5
Use the distributive property to multiply 7 by k-3.
7k-21-3k=-5
Subtract 3k from both sides.
4k-21=-5
Combine 7k and -3k to get 4k.
4k=-5+21
Add 21 to both sides.
4k=16
Add -5 and 21 to get 16.
k=\frac{16}{4}
Divide both sides by 4.
k=4
Divide 16 by 4 to get 4.
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