I have a plane and a loop cut that is highlighted as shown in the image above. I wanted to know how do I scale the plane to the exact dimensions of the loop cut?
You may do it using a snapping tool. First select the edge loop in Edit Mode (Alt+RMB) and snap the cursor to it (Shift+S-->Cursor to Selected). Then select the plane in Object Mode and press Shift+S-->Selection to Cursor [Offset]).
You may also snap the plane to the corner of the edge loop in Object Mode. Then change the pivot point type to 3D Cursor, snap the cursor to the corner of the plane in Edit Mode with Shift+S-->Cursor to Selected and then scale it until it fits the edgeloop.
You could also simply select the loop. Duplicate it. Then fill the duplicate (f key). Check your normals to make sure they are going the right direction.