Question
Sun June 19, 2011 By:
 

solve 6/x+y=7/x-y +3,1/2(x+y) =1/3(x-y),where x+y?0 and x-y?0.

Expert Reply
Sun June 19, 2011

Let 

So, now the given equations become:

6u – 7v = 3           ... (1)

3u – 2v = 0           ... (2)

Multiplying (2) by 2, we get,

6u = 4v

Putting this value in (1),

4v – 7v = 3

– 3v = 3

v = –1

So, u = -2/3

Substituting the values of u and v in (A), we get,

x + y = -1              ... (3)

x - y = -3/2 or 2x - 2y = -3      ... (4)

Multiplying (3) by 2, we get,

2x + 2y = -2         ... (5)

Adding (4) and (5), we get,

4x = -5

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