Answer: (-3a)/(b^2)
Restrictions are that 'a' and 'b' cannot be zero. We could write [tex]a \ne 0[/tex] and [tex]b \ne 0[/tex] as shorthand.
The restrictions are put in place to ensure that you can't divide by zero.
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Explanation:
The coefficients -12 and 4 divide to -12/4 = -3 which is the coefficient for the answer in the numerator.
The 'a' terms divide to (a^3)/(a^2) = a^(3-2) = a^1 = a. We subtract the exponents to simplify.
The b terms are handled in a similar manner to get (b^5)/(b^7) = b^(5-7) = b^(-2) = 1/(b^2)
Putting all three results together has us end up with (-3a)/(b^2) where neither 'a' nor b are zero to prevent a division by zero error. We cannot have 0 in the denominator.
