Question

what is the extension line ?​

Answer 1

Extension Lines and Dimension Lines. ... They are drawn perpendicularly when connecting dimension lines. For example, an extension line will reach beyond a complex object to connect with a dimension line that may give a specific height or distance. The extension line is an extension on the object.

Answer 2

extension lines on that lines that extend from object outside or point on object to a place outside the image area . define areas for dimensions .

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