1. **State the problem:** We have a circle with center O and points A, B, C, D on the circumference. DB is a diameter, and AC intersects DB at point P. Given lengths are AP = 12 cm, PC = 7 cm, and PB = 6 cm. We need to find the area of the circle.
2. **Use the intersecting chords theorem:** When two chords intersect inside a circle, the products of the segments of each chord are equal. That is,
$$AP \times PC = PB \times PD$$
3. **Calculate PD:** We know AP = 12, PC = 7, PB = 6, so
$$12 \times 7 = 6 \times PD$$
$$84 = 6 \times PD$$
Divide both sides by 6:
$$\cancel{6} \times PD = \frac{84}{\cancel{6}}$$
$$PD = 14$$
4. **Find the length of diameter DB:** Since DB is a diameter, and P lies on DB, the length DB = PB + PD = 6 + 14 = 20 cm.
5. **Calculate the radius:** Radius $r = \frac{DB}{2} = \frac{20}{2} = 10$ cm.
6. **Calculate the area of the circle:**
$$\text{Area} = \pi r^2 = \pi \times 10^2 = 100\pi$$
7. **Final answer:**
$$\text{Area} \approx 100 \times 3.142 = 314.2 \text{ cm}^2$$
Rounded to 3 significant figures, the area is **314 cm\textsuperscript{2}**.
Circle Area Fff683
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