When I wanted to insert a formula into Libreoffice today, the option was greyed out. Luckily I figured out that the libreoffice-math package is required (Google didn't help much). So it seems this package is not automatically installed together with Solus. I recommend changing that, because I don't think every noob is able to figure out there is an extra package required (in other distributions like Ubuntu it's installed automatically).
Sorry if that's the wrong place for this request, or if Solus users aren't supposed to be noobs.