Create a flush boundary between two polygons by making a shared edge

Draw two polygons

Draw two polygons side by side.

Make each polygon have an edge that is parallel to an edge on the other polygon.

These two edges will be combined to make the shared edge.

To learn more about drawing polygons, visit this link:

• Draw a polygon - (Polygon Tool)

Make a flush boundary on two edges

1. Choose which polygon is going to have the edge that stays in place. We’ll call this the first polygon.
    
2. Select the "Edit/Measure Tool" in the top toolbar.

   Or you can press the "Q" button on your keyboard.

    
3. On the second polygon, hover over the first corner of the edge.
   You will see a blue square appear.
    
4. Click and drag the corner until it is on top of the appropriate corner on the first polygon.
    
5. Let go when you see the black circle appear.
    
6. On the second polygon, hover over the second corner of the edge.
   You will see a blue square appear.
    
7. Click and drag the corner until it is on top of the appropriate corner on the first polygon.
    
8. Let go when you see the black circle appear.
   You will see there is now a flush boundary between the two polygons.