Question

Combine these radicals.



–66
–54

-6/136
-6/16

Answer 1

I assume you meant square roots. I'll do both likely interpretations.

If the problems are
1) -√66 - √54
2) -6√136 - 6√16

1) -√66 - √54
√66 = √6·√11, √54 = √(9·6) = 3√6
So -√66 - √54 = -√6(√11 + 3).

2) -6√136 - 6√16
√136 = √(4·34) = 2√34, √16 = 4
So -6√136 - 6√16 = -6(2√34) - 6(4) = -12√34 - 24 = -12(√34 + 2).

If instead you literally meant the fractions -6/136 and -6/16, their sum is
-6/136 - 6/16 = -3/68 - 3/8 = -57/136.

Tell me which interpretation you meant if you want more detail.