how to define a line dimention

[gchen-4]

In the attached screen shot, how do I define the upper line with a length instead of using the angels?

I need it to be set to 25mm.

Thanks,

Gil.

[RonSt.Pierre]

Several options

1) create another dimension from the centerline to the "point of the angle", this will cause the angle dimension to disappear

2) you can create a symmetry constraint about the centerline between the endpoint left (-7,2) with the endpoint on the right which will become (7,2) and one dim will have to go away, either the 7 or the 14

3) make the angled lines have a constraint of equal lengths.