Q1 of 71 Page 65

Solve the following pairs of equations by cross multiplication method:

5x + 8y = 18, 2x — 3y = 1

Given equations are


5x + 8y = 18, 2x — 3y = 1


Change the given equations to the form,


a1x + b1y + c1 = 0 and a2x + b2y + c2 = 0 …(i)


⇒ 5x + 8y – 18 = 0 and


2x — 3y – 1 = 0


On comparing with (i) we get,


a1 = 5, b1 = 8, c1 = – 18; a2 = 2, b2 = – 3, c2 = – 1


Applying cross multiplication method which says,



Putting the given values in the above equation we get,







Similarly,



∴The solution of the pair of equations is (2, 1).


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