1. **Stating the problem:**
We need to find the area of the sector ALB of a circle with center L, where AL = 14 cm, angle LAC = 25°, and AC = BC.
2. **Understanding the problem:**
Since AC = BC, triangle ABC is isosceles with AC = BC.
Angle LAC = 25° is given, and AL is the radius of the circle (14 cm).
3. **Find the central angle of sector ALB:**
Since AC = BC, angle LAC = angle LBC = 25°.
Therefore, angle ALB = angle LAC + angle LBC = 25° + 25° = 50°.
4. **Formula for the area of a sector:**
$$\text{Area of sector} = \frac{\theta}{360^\circ} \times \pi r^2$$
where $\theta$ is the central angle in degrees and $r$ is the radius.
5. **Calculate the area:**
$$\text{Area} = \frac{50}{360} \times \pi \times 14^2 = \frac{50}{360} \times \pi \times 196$$
6. **Simplify the fraction:**
$$\frac{50}{360} = \frac{5}{36}$$
7. **Calculate the area numerically:**
$$\text{Area} = \frac{5}{36} \times 196 \times \pi = \frac{5 \times 196}{36} \times \pi = \frac{980}{36} \times \pi = \frac{245}{9} \times \pi$$
8. **Approximate the value:**
Using $\pi \approx 3.1416$,
$$\text{Area} \approx \frac{245}{9} \times 3.1416 = 27.222 \times 3.1416 \approx 85.5 \text{ cm}^2$$
9. **Check the options:**
None of the options match 85.5 cm² exactly, so re-examine the problem.
10. **Reconsider the angle ALB:**
Since AC = BC and angle LAC = 25°, triangle ABC is isosceles with vertex angle at C.
Angle ALB is the central angle subtending arc AB.
Because AC = BC, angle ACB = 180° - 2*25° = 130°.
11. **Central angle ALB is twice angle ACB:**
In a circle, the central angle is twice the inscribed angle subtending the same arc.
Therefore, angle ALB = 2 * 130° = 260°.
12. **Calculate the sector area with corrected angle:**
$$\text{Area} = \frac{260}{360} \times \pi \times 14^2 = \frac{260}{360} \times \pi \times 196$$
13. **Simplify the fraction:**
$$\frac{260}{360} = \frac{13}{18}$$
14. **Calculate the area numerically:**
$$\text{Area} = \frac{13}{18} \times 196 \times \pi = \frac{2548}{18} \times \pi = 141.56 \times \pi$$
15. **Approximate the value:**
$$141.56 \times 3.1416 \approx 444.5 \text{ cm}^2$$
This is too large compared to options, so the previous step is incorrect.
16. **Alternative approach:**
Since AC = BC and angle LAC = 25°, triangle ALC is isosceles with AL = LC = 14 cm.
Angle LAC = 25°, so angle ALC = 25°.
Therefore, angle ACB = 180° - 2*25° = 130°.
17. **Angle ALB is the central angle subtending arc AB, which equals 2 * angle ACB = 2 * 130° = 260°.
But sector angle cannot be more than 180° for minor sector.
18. **Assuming minor sector angle is 100° (360° - 260°):**
Calculate area with $\theta = 100^\circ$:
$$\text{Area} = \frac{100}{360} \times \pi \times 14^2 = \frac{5}{18} \times \pi \times 196 = \frac{980}{18} \times \pi = 54.44 \times \pi$$
19. **Approximate:**
$$54.44 \times 3.1416 \approx 171.1 \text{ cm}^2$$
20. **Final answer:**
The area of sector ALB is approximately 171.1 cm².
**Answer: E. 171,1 cm²**
Sector Area 6272Ec
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