Mower Blade Replacement 

I drove it through the woods, cutting 3/4” brush 👀. Yeah that Impact holds no prisoners. Come out or break off are the only options.

I found that sharpening them with an angle grinder with a flap disc works really good. Just sharpen until you see a burr, fold it over while wearing gloves, clean it up with a flat file, then balence it of course. But yours were definitely too worn.