-6/7-5/21

To solve the expression -6/7 - 5/21, you first need to find a common denominator for the two fractions. In this case, the least common multiple of 7 and 21 is 21.

So, -6/7 becomes -18/21 when multiplied by 3 to get the common denominator, and 5/21 remains the same.

Now, you can subtract the fractions:

-18/21 - 5/21 = -23/21

Therefore, the result of -6/7 - 5/21 is -23/21.