What to do
For each shape, count the sides and the vertices (corners) carefully. The goal is to give the exact count, then simplify the final answer if it is written as an expression or a list.
Step-by-step method
- Look at one shape at a time.
Focus on the outer boundary only. Ignore interior markings unless they change the shape itself.
- Count the sides.
A side is a straight edge. Move around the shape once and count each edge exactly once.
- Count the vertices.
A vertex is a corner where two sides meet. Count each corner once.
- Match your counts.
For common polygons, the number of sides and vertices should agree.
- Simplify the final answer.
If your answer is written as a combined result, reduce it to the simplest exact form.
Check your work
- Recount by tracing the shape with your finger or pencil.
- Make sure no side or corner is counted twice.
- For polygons, check that every side has two endpoints and every vertex connects two sides.
Helpful tip
If the shape is irregular, start at any corner and go around in one direction until you return to the start. This helps you count consistently without skipping anything.