<PRE><B>Question 903875</B>
The real trouble then is how to simplify a rational expression.


Very complicated fraction when forming the composition, {{{((5(9/(3t+7)))/((9/(3t+7))-1))}}}


{{{(5(3t+7)/9)/((9/(3t+7))-(3t+7)/(3t+7)))}}}


{{{(5(3t+7)/9)/((2-3t)/(3t+7))}}}


Division by a fraction is multiplying by the reciprocal,

{{{((5(3t+7))/(9)) * ((3t+7)/(2-3t))}}}


Nothing to simplify so just perform the multiplications and simplify what is possible from that:


{{{(5(9t^2+42t+49))/(18-27t)}}}


{{{highlight((45t^2+210t+245)/(18-27t))}}}

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