If 19x-17y=55 and 17x-19y=53, then the value of x-y is . . .

Question : If 19x-17y=55 and 17x-19y=53, then the value of x-y is 

a)1/3

b) -3

c) 3

d) 5

Doubt by Zoha

Solution :

19x-17y=55 — (1)

17x-19y=53 — (2) 

Adding equation (1) and (2) 

19x-17y=55 

17x-19y=53
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36x-36y=108
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36(x-y)=108

x-y=108/36

x-y=3 

Hence, c) is the correct option.