Polygon Angles 99Aa99
1. **Problem Statement:** Find the unknown angle $x$ in each polygon given the other interior angles.
2. **Formula:** The sum of interior angles of a polygon with $n$ sides is given by:
$$\text{Sum of interior angles} = (n-2) \times 180^\circ$$
3. **Left Polygon (Hexagon):**
- Number of sides $n=6$
- Sum of interior angles:
$$ (6-2) \times 180^\circ = 4 \times 180^\circ = 720^\circ $$
- Known angles: $70^\circ, 142^\circ, 130^\circ, 30^\circ, 141^\circ$
- Sum of known angles:
$$70 + 142 + 130 + 30 + 141 = 513^\circ$$
- Find $x$:
$$x = 720 - 513 = 207^\circ$$
4. **Right Polygon (Star-shaped, 4 sides):**
- Number of sides $n=4$
- Sum of interior angles:
$$ (4-2) \times 180^\circ = 2 \times 180^\circ = 360^\circ $$
- Known angles: $20^\circ, 85^\circ, 34^\circ$
- Sum of known angles:
$$20 + 85 + 34 = 139^\circ$$
- Find $x$:
$$x = 360 - 139 = 221^\circ$$
**Final answers:**
- Left polygon: $x = 207^\circ$
- Right polygon: $x = 221^\circ$