Question

Find the following when a = -2, b = 3, c = -1/3
a^3 - 6c

Answer 1

Easy, just plug n chug

a=-2 b=3 and c=-1/3

-2^3=-8

-6(-1/3)=2

-8+2=-6

Thus, your answer is, 6. 

The b was extra unnecessary information.

Answer 2

That would be -34.

-2 times -2 times -2 minus 6 times -1/3

                                                 6/1 times -1/3 (cross multiply)

-16 minus 18= -34