1. **Problem Statement:** Find the area of a regular heptagon and a regular octagon given the perimeter $P=12$.
2. **Formula for area of a regular polygon:**
$$\text{Area} = \frac{1}{4} n s^2 \cot\left(\frac{\pi}{n}\right)$$
where $n$ is the number of sides and $s$ is the side length.
3. **Calculate side length $s$:**
Since perimeter $P=12$, and $P = n \times s$, we have
$$s = \frac{P}{n} = \frac{12}{n}$$
4. **Calculate area of the heptagon ($n=7$):**
$$s_7 = \frac{12}{7}$$
$$\text{Area}_7 = \frac{1}{4} \times 7 \times \left(\frac{12}{7}\right)^2 \times \cot\left(\frac{\pi}{7}\right)$$
5. **Calculate area of the octagon ($n=8$):**
$$s_8 = \frac{12}{8} = 1.5$$
$$\text{Area}_8 = \frac{1}{4} \times 8 \times (1.5)^2 \times \cot\left(\frac{\pi}{8}\right)$$
6. **Evaluate cotangents and simplify:**
- Approximate $\cot\left(\frac{\pi}{7}\right) \approx 2.076$.
- Approximate $\cot\left(\frac{\pi}{8}\right) = 1 + \sqrt{2} \approx 2.414$.
7. **Calculate numeric values:**
$$\text{Area}_7 = \frac{7}{4} \times \frac{144}{49} \times 2.076 = \frac{7 \times 144 \times 2.076}{4 \times 49} \approx 10.66$$
$$\text{Area}_8 = 2 \times 2.25 \times 2.414 = 10.87$$
**Final answers:**
- Area of heptagon $\approx 10.66$
- Area of octagon $\approx 10.87$
Polygon Area 378Dca
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