SolidWorks Tutorials on Demand

If you set your circles to construction and the use lines and 3 point arcs and make the arcs tangent, that should work. Save the need trim and then they will automatically change if you ever adjust dimensions.

If you want sharp corners make the lines coincident by right clicking and highlighting them and the box on the left select "coincident in the relations box. If one point (end line)is fixed to a tangent point on the circle, you will have to clear that point first by clicking on it and deleting it's relationship.

If you want to keep the corner radii then make the line ends coincident to the circle then trim the inner portion of the circle using the trim tool found in Tools> Sketch Tools>Trim.

i want to make path for chain and sprocket mechanism in which inner side of circle have no realtion by using power trim and outer one act as a line with lines when i used power trim it completely diappeared. what will i do

Do you understand the relations that need to be met before trimming? If you have a blue dot showing at the end of a line it is not related to anything so when you trim the circle it will naturally be taken out because there is no boundary to stop the trim action. Try to trim the line that is unneeded in the path thus leaving it trimmed to the circle. Once the lines are coincident and tangent to the circle you should be able to trim the circle by selecting the area that you want to remove...the part of the circle inside your pattern, not the outer edge. where you select it drives what it cuts.

First, drag that upper line from the blue dot inwards till it reaches the circle.

Then, click and drag the cursor over the lines you want to trim...