SOLUTION: What is the answer for thes: 2+x/7=y/4 3+y/5=x/3

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Question 90853: What is the answer for thes:
2+x/7=y/4
3+y/5=x/3
Answer by chitra(359) About Me  (Show Source):
You can put this solution on YOUR website!
The given equations are:

+2+%2B+%28x%2F7%29+=+%28y%2F4%29+

3+%2B+%28y%2F5%29+=+%28x%2F3%29+

Taking LCM, this can be written as:


%28%2814+%2B+x%29%2F7%29+=+%28y%2F4%29

%2815+%2B+y%29%2F5%29+=+%28x%2F3%29

Now cross multiplying and writing x and y terms on one side, we get:

56 + 4x = 7y ----------(1)

45 - 5x = - 3y ---------(2)


Now lets solve both the equations simultaneously, Multiply eqn (1) by 3 and (2) by 7.

We get:

168 + 12x = 21y
315 - 35x = - 21y
on solving them we get -23x = -483
==> x = 21
substituting the value of x we get the value of y
==> y = 20

thus the solution