Answer:
k=2
Step-by-step explanation:
3k-k+5k-7=7
2k+5k=7+7
7k=14
k=14/7
[tex] \: \: \: \: \: \: \: \: 3k - k + 5k - 7 = 7 \\ = > 8k - k = 7 + 7 \\ = > 7k = 14 \\ = > k = \frac{14}{7} \\ = > k = 2[/tex]