Join our CAD community forums where over 25,000 users interact to solve day to day problems and share ideas. We encourage you to visit, invite you to participate and look forward to your input and opinions. Acrobat 3D, AutoCAD, Catia, Inventor, IronCAD, Creo, Pro/ENGINEER, Solid Edge, SolidWorks, and others.
Grab the dimension line with your mouse & drag it, whilst dragging, hover over the dimension you want to align with, a small yellow dot will appear somewhere on the line of this dimension, let go of the mouse button & the dimensions will align. Sometimes yo have to search around a bit to get the yellow dot but it usually works,
To align dimensions, first, highlight the dimension you want to align,then hoover over the dimension you want to be in alignment. There will appear a yellow dot on that dimension. That means Inventor see the alignment. Then just click and your original dimension should align itself. Sometime you have to play with it a little to get the feel of it.