Choose the Maintain Relationships command 
from the Home tab→Relate group or the Sketching tab→Relate group.
Click one of the following commands:
Smart Dimension
Distance Between
Angle Between
When Maintain Relationships is set, the dimensions you place will be driving dimensions by default.
Tip:
To change a driving dimension to a driven dimension, select a driving dimension and then click the Driving button on the Dimension command bar.
—When this option is set, it is driven.
—When this option is set, it is driving.
If the Driving button is not available, select the Maintain Relationships command.
To place a horizontal or vertical dimension regardless of the orientation of the element, press and hold the Shift key while placing the dimension.
You can use the mouse scroll wheel to increase or decrease the initial dimension value in 5 percent increments. To do this, click the dimension you want to change and move the scroll button forward to increase the dimension or backward to decrease it.
On the Solid Edge options→Helpers page, if the option Enable Value Changes Using the Mouse Wheel is unchecked, use the Ctrl+mouse wheel to change a dimension value. If the option is checked, use the mouse wheel to change a dimension.