SOLUTION: Can you please explain how to solve this: rational expression division z+5/z divided by 3z+15/4z

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Question 196802: Can you please explain how to solve this:
rational expression division z+5/z divided by 3z+15/4z

Found 2 solutions by solver91311, Anthea Lawn:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Just like dividing any other fractions. Invert the divisor and multiply.


John


Answer by Anthea Lawn(22) About Me  (Show Source):
You can put this solution on YOUR website!
No worries - one fraction divided by another is the same as the first fraction MULTIPLIED by the second fraction UPSIDE DOWN.
In other words a half divided by a third is equal to a half multiplied by three = one and a half.
In your case, we'll flip the second fraction upside down and then multiply :
%28z%2B5%29%2Fz X 4z%2F%283z%2B15%29

The 4z on the top cancels out with the z on the bottom to leave a 4.
Now we have 4 X %28z%2B5%29%2F%283z%2B15%29


(3z + 15) is three times (z+5) so we can cancel these out too to give a final answer of 4/3 = one and a third.
This is true for all values of z. (except where z = 0 for which (z+5)/z is clearly a division by zero)