Answer:
-18 b^-4= -18/b^4
Step-by-step explanation:
-3b^4(6b^-8)
Combine coefficients
-3*6 = -18
Combine exponents since the bases are the same, x^y * x^z = x^(x+z)
b^4 *b^ -8
b^(4+-8)
b^ -4
Put back together
-18 b^-4
We also know that x^-y = 1/x^y
-18/b^4
