SOLUTION: (X+1)/7 - (X-3)/5 = 4/5

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Question 14719: (X+1)/7 - (X-3)/5 = 4/5
Answer by Drpengui(15) About Me  (Show Source):
You can put this solution on YOUR website!
%28x%2B1%29%2F7-%28x-3%29%2F5+=+%284%2F5%29problem
create equal denominators

distribute the 5 and the 7 and multiply (4*7) and (5*7)
%285x%2B5%29%2F35-%287x-21%29%2F25+=+%2828%2F35%29
add (5x+5) to -(7x-21) (make sure you distruibute the negative)
%285x%2B5-7x%2B21%29%2F35=28%2F35
then because they both have 35 as the denominator you can muliply both sides by 35 to cancel them out
35%2A%28%285x%2B5-7x%2B21%29%2F35%29=%2828%2F35%29%2A35
5x%2B5-7x%2B21=28
then combine like terms
-2x%2B26=28
then subtract 26 from both sides
-2x=2
then divide by -2
x=-1