I dont understand this. could someone give me step by step what the answer would be If?

Questions: If one solution of a quadratic equation is 7-13i, what would the second solution be?

Question 2: solve these, step by step using indicated operations with work!

1. (4-3i) (-7+21)
2. (-7+6i)+(2-3i)+(4+5i)
3. (-6-i)/4-2i
4. (-2-7i)(-2+7i)
5. (5-3i)-(-2-6i)
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