To edit lines and polygons, you need to first select the feature, enable the Vertex Toolbar and then reshape the feature by dragging the handles (red circles).
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2. On the Map Tools pane, click the More Tools button and then click Editing. The Editing window opens.
3. In the Edit Layer field, select the layer where you want to edit the features.
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6. Select the feature with the tool. The results are displayed in the Results window and the features are shown on the map.
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9. Click Update Vertex Changes to save the changes.