1. **Problem:** Given $a = -7i$ and $b = \frac{1}{6}i$, find $8(a + 2b)$.
2. **Formula and rules:** To solve this, use the distributive property and combine like terms. Remember that $i$ is the imaginary unit.
3. **Step-by-step solution:**
- Calculate $2b$: $$2b = 2 \times \frac{1}{6}i = \frac{2}{6}i = \frac{1}{3}i$$
- Add $a$ and $2b$: $$a + 2b = -7i + \frac{1}{3}i = \left(-7 + \frac{1}{3}\right)i = \left(-\frac{21}{3} + \frac{1}{3}\right)i = -\frac{20}{3}i$$
- Multiply by 8: $$8(a + 2b) = 8 \times -\frac{20}{3}i = -\frac{160}{3}i$$
4. **Final answer:** $$8(a + 2b) = -\frac{160}{3}i$$
Complex Expression 1Cefe2
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