Problem in joining two objects
Hello! I'm using Illustrator to design cut lines to my vinyl cutter and I'm having problems with overlaping lines.
For example, I want that three retangles to be cut using the same lines. If every retangle have its own line, I'll have double lines that will make the cutter to cut twice. I want them to share the same line.
But, I'm not being able to do that. I'm here for hours and Ctrl J doesn't work and I don't know why. I want simply to connect the bottom retangle to the two top retangles

