How to implement of Line

• From the draw menu, chose Line.
• Specify the start point.
• You can use the pointing device or enter a coordinate on the command line.
• Complete the first line segment during the LINE command, enter u or chose Undo on the toolbar.
• Specify the endpoints of any additional line segments.
• Press ENTER to end  or c to close a series of line segments.
• To start a new line at the endpoint of the last line drawn, start the LINE  command again and press ENTER at the specify Start Point prompt.  

How We Can Entering the Point in AutoCAD

• Draw a box using Polar Co-ordinate in put. Start the Line Command
• Begin at point 8,2 then enter:
• Type @ 1<45 to draw the first line.
• Next enter @ 1<135 then
• @ 1<225 then
• @ 1 <315 (or C to close)  
• Draw rectangle using this system

Detail of Table with Dimensions

Detail of Table Drawing

What is Polar Coordinates

The fixed horizontal line in as system of polar coordinates from which the object is drawn by giving distance with angle.

i.e Distance = length < (symbol)

Angle= to which direction the object is required.        

                                                                                                             

                                                                                                                                                                                           

Type of Relative Co-ordinates

Coordinates that are defined in terms of their distance from a given starting point, rather than from the origin (intersection of two axes).

Type of Entering Point Style.

You can enter points directly on the command line using three different system.

Absolute Co-ordinate.

Relative Co-ordinate.

Polar Co-ordinate. 

What is the X,Y Co-ordinate system

Absolute Coordinates

Coordinates that are defined in terms of their distance from the origin, that point where the axes intersect.

Syntax:-

         X,Y

i.e. only give two values separated

by comma.

The X, Y, Z Coordinate System.

·         AutoCAD uses points determine where an object is located.

·        There is an origin where it begins counting from. This point is (0,0). Every object is       
     located in relation to the origin.

·        If you were to draw a lone straight out to the right from the origin, this would be                      considered the positive-axis.

·        If you were to draw a line straight up, this would be the positive Y-axis.

·        When you are working with points, X always comes first. The other point shown is                 (-10,-5). This means that the point is 10 units in the negative X-axis (left) and 5 units in         the negative Y-axis (down).