Answer :

luana
[tex]Greatest\ common\ factor\ is\ the\ highest\ number\ by\ which\ 51\ and\ 85\\ can\ be\ divided\\\\ 51:51\\\\ 85:5\\ 17:17\\\\GCF=1\\\\Greatest\ common\ factor\ of\ 51\ and\ 85\ is\ equal\ to\ 1. [/tex]