1. **State the problem:** Solve for the complex number $z$ in the equation $$(3-5i)(z+2i) = i.$$
2. **Use the distributive property:** Expand the left side:
$$ (3-5i)(z+2i) = (3-5i)z + (3-5i)(2i). $$
3. **Calculate the product $(3-5i)(2i)$:**
$$ (3-5i)(2i) = 3 \cdot 2i - 5i \cdot 2i = 6i - 10i^2. $$
Since $i^2 = -1$, this becomes
$$ 6i - 10(-1) = 6i + 10 = 10 + 6i. $$
4. **Rewrite the equation:**
$$ (3-5i)z + 10 + 6i = i. $$
5. **Isolate $(3-5i)z$:**
$$ (3-5i)z = i - 10 - 6i = -10 - 5i. $$
6. **Solve for $z$ by dividing both sides by $(3-5i)$:**
$$ z = \frac{-10 - 5i}{3 - 5i}. $$
7. **Rationalize the denominator:** Multiply numerator and denominator by the conjugate of the denominator $(3 + 5i)$:
$$ z = \frac{(-10 - 5i)(3 + 5i)}{(3 - 5i)(3 + 5i)}. $$
8. **Calculate the denominator:**
$$ (3 - 5i)(3 + 5i) = 3^2 - (5i)^2 = 9 - (-25) = 9 + 25 = 34. $$
9. **Calculate the numerator:**
$$ (-10)(3) + (-10)(5i) + (-5i)(3) + (-5i)(5i) = -30 - 50i - 15i - 25i^2. $$
Since $i^2 = -1$,
$$ -25i^2 = -25(-1) = 25. $$
So numerator becomes
$$ -30 - 65i + 25 = (-30 + 25) - 65i = -5 - 65i. $$
10. **Write $z$ as:**
$$ z = \frac{-5 - 65i}{34} = -\frac{5}{34} - \frac{65}{34}i. $$
11. **Simplify fractions:**
$$ -\frac{5}{34} = -0.1470588..., \quad -\frac{65}{34} = -1.9117647... $$
So approximately
$$ z \approx -0.147 - 1.912i. $$
**Final answer:**
$$ z = -\frac{5}{34} - \frac{65}{34}i. $$
Solve Complex 11Acc1
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