Q. 64.3( 4 Votes )
If 
and 
then
A. x = 1/2, y = 3/2
B. x = 5/2, y = 1/2
C. = 3/2, y = 1/2
D. x = 1/2, y = 5/2
Answer :
We have,
…(i)
…(ii)
Now, substituting 
and 
in (i) and (ii) we get:
3u + 2v = 2 …(iii)
9u – 4v = 1 …(iv)
Multiplying (iii) by 2 and adding it with (iv) we get:
6u + 9u = 4 + 1
Multiplying again (iii) by 2 and then subtracting it from (iv), we get:
6v + 4v = 6 – 1
∴ x + y = 3 …(v)
And, x – y = 2 …(vi)
Now, by adding (v) and (vi) we get:
2x = 3 + 2
Substituting the value of x in (v), we get
Hence, option B is correct
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