Polygons From Points
1. **Problem statement:** Given seven points on a plane, no three of which are collinear, we want to find how many polygons can be drawn using these points as vertices.
2. **Key idea:** A polygon is formed by choosing at least 3 points from the given points. Since no three points are collinear, every subset of points with size 3 or more forms a polygon.
3. **Formula:** The number of polygons is the sum of combinations of 7 points taken $k$ at a time for $k=3$ to $7$:
$$\sum_{k=3}^{7} \binom{7}{k}$$
4. **Calculate each term:**
- $\binom{7}{3} = \frac{7!}{3!4!} = 35$
- $\binom{7}{4} = \frac{7!}{4!3!} = 35$
- $\binom{7}{5} = \frac{7!}{5!2!} = 21$
- $\binom{7}{6} = \frac{7!}{6!1!} = 7$
- $\binom{7}{7} = 1$
5. **Sum all:**
$$35 + 35 + 21 + 7 + 1 = 99$$
6. **Answer:** There are $\boxed{99}$ polygons that can be drawn from the seven points with no three collinear.