Answer:
Explanation:
" / " indicates "division" and should not be used in this context.
If you meant: -2 square root 13 plus 19 square root 13, the simplest result would be 17 square root 13.
Note that if you click on the "omega" symbol (below), a menu of symbols will appear, including the square root symbol √.
Then: -2√13 + 19√13 = 17√13.