Solve each of the following systems of equations by using the method of cross multiplication:

We have,

…(i)


…(ii)


Let 1/x = p and 1/y = q. Now,


From equation (i), p + q = 7


p + q – 7 = 0 …(iii)


From equation (ii), 2p – 3q = 17


2p + 3q – 17 = 0 …(iv)


From equation (iii), we get a1 = 1, b1 = 1 and c1 = - 7


And from equation (iv), we get a2 = 2, b2 = 3 and c2 = - 17


Using cross multiplication,







and


p = 4 and q = 3


x = 1/4 and y = 1/3 [ p = 1/x and q = 1/y]


Thus, x = 1/4, y = 1/3


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