Solve for x and y:

, x + y = 2ab

We have,


b2x + a2y = a3b + ab3 …(i)


x + y = 2ab …(ii)


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


Lets multiply equation (ii) by a2, so that variable y in both the equations have same coefficient.


Recalling equations (i) & (ii),


b2x + a2y = a3b + ab3


x + y = 2ab [×a2]



b2x – a2x = - a3b + ab3


(b2 – a2)x = ab(b2 – a2)


x = ab


Substitute x = ab in equations (i)/(ii), as per convenience of solving.


Thus, substituting in equation (ii), we get


(ab) + y = 2ab


y = ab


Hence, we have x = ab and y = ab.


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