Tutorial - Equation driven part in SolidWorks?

Here is the tutorial.
Step 1:
Front Plane>>Sketch.
Step 2:
Draw a center point rectangle at origin. Smart Dimension one side.
Step 3:
Smart Dimension other side and in value input press =.
Step 4:
Select the 1st dimension and then *0.75. This will be expression y=0.75*x.
Step 5:
Draw a circle at origin and smart dimension by the first dimension /3. i.e.z=x/3.
Step 6:
Extrude it.
Step 7:
Double click the part. It will show all the dimensions.
Step 8:
Double click the extrusion dimension and it's relation with the height of part also *1.25. i.e. a=1.25*x.
Step 9:
Rebuild part.
Step 10:
When we change the height of part from 100 to 150.
Step 11:
Click Rebuild and we have new dimensions.
Thanks for reminding me...