1. **State the problem:** Find the area of a regular pentagon with an apothem (distance from center to a side) of 19 m.
2. **Formula:** The area $A$ of a regular polygon is given by
$$A = \frac{1}{2} \times P \times a$$
where $P$ is the perimeter and $a$ is the apothem.
3. **Important rules:**
- A regular pentagon has 5 equal sides.
- The apothem is perpendicular to each side and helps calculate the area.
4. **Find the side length:**
The apothem $a$ relates to the side length $s$ by
$$a = \frac{s}{2 \tan(\pi/5)}$$
Rearranged,
$$s = 2a \tan(\pi/5)$$
Substitute $a=19$:
$$s = 2 \times 19 \times \tan(36^\circ)$$
Calculate $\tan(36^\circ) \approx 0.7265$:
$$s = 38 \times 0.7265 = 27.607$$
5. **Calculate perimeter:**
$$P = 5 \times s = 5 \times 27.607 = 138.035$$
6. **Calculate area:**
$$A = \frac{1}{2} \times P \times a = \frac{1}{2} \times 138.035 \times 19$$
$$A = 69.0175 \times 19 = 1311.3325$$
7. **Round to nearest hundredths:**
$$\boxed{1311.33 \text{ m}^2}$$
This is the area of the regular pentagon with apothem 19 m.
Pentagon Area 3E84A8
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