Question 199341
Remember negative  exponent  is  reciprocal,,,,a^-2 = 1/a^2
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AND ,  to  divide  common  bases,,,substract  exponents,,,,a^4/a^2=a^(4-2) = a^2 
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(1)  (r^-4)(-6r^2t^2) = -6 r^-2t^2= -6t^2 / r^2
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(2)  w^3 / (-6w^-6) = w^9/-6 = (-1/6) w^9
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(3) k^6 / (k^3)^5 = k^6/k^15 =k^-9 = 1/k^9
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(4) t^-9 / q^-9 = q^9/t^9 = (q/t)^9
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check  by  assigning  numbers  to  variables  and  checking  original  and  answer,,,all  ok