# 2.4E: Complex Numbers (Exercises)

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For the following exercises, use the quadratic equation to solve.

26. $$x^{2}-5 x+9=0$$
27. $$2 x^{2}+3 x+7=0$$

For the following exercises, name the horizontal component and the vertical component.

28. $$4-3 i$$
29. $$-2-i$$

For the following exercises, perform the operations indicated.

30. $$(9-i)-(4-7 i)$$
31. $$(2+3 i)-(-5-8 i)$$
32. $$2 \sqrt{-75}+3 \sqrt{25}$$
33. $$\sqrt{-16}+4 \sqrt{-9}$$
34. $$-6 i(i-5)$$
35. $$(3-5 i)^{2}$$
36. $$\sqrt{-4} \cdot \sqrt{-12}$$
37. $$\sqrt{-2}(\sqrt{-8}-\sqrt{5})$$
38. $$\frac{2}{5-3 i}$$
39. $$\frac{3+7 i}{i}$$

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