Solve for x and y:

x + y = 5xy, 3x + 2y = 13xy (x ≠ 0, y ≠ 0)

We have

x + y = 5xy


and 3x + 2y = 13xy


where x≠0 and y≠0


Lets simplify these equations.


x + y = 5xy


Dividing the equation by xy throughout,




Assuming p = 1/y and q = 1/x, we get


p + q = 5 …(i)


Also, 3x + 2y = 13xy


Dividing the equation by xy throughout,




Assuming p = 1/y and q = 1/x, we get


3p + 2q = 13 …(ii)


To solve these equations, we need to make one of the variables (in both the equations) have same coefficient.


Lets multiply eq.(i) by 2, so that variable q in both the equations have same coefficient.


Recalling equations (i) & (ii),


p + q = 5 [×2]


3p + 2q = 13



- p = - 3


p = 3


Substitute p = 3 in eq.(i)/eq.(ii), as per convenience of solving.


Thus, substituting in eq.(i), we get


3 + q = 5


q = 5 – 3


q = 2


Thus, p = 3 and q = 2


As q = 1/x,


2 = 1/x


x = 1/2


And p = 1/y


3 = 1/y


y = 1/3


Hence, we have x = 1/2 and y = 1/3


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