Q1 of 71 Page 68

Solve the following pairs of linear equations:

x > 0, y > 0




Putting these value in given equations, we get




So, the given equations transforms into linear equation in two variables i.e.


3a + 4b = 2 … (i)


60a + 84b = 41 …..(ii)


Multiply (i) by 20,


60a + 80b = 40 …. (iii)


60a + 84b = 41 …..(ii)


Subtract (iii) from (ii),


60a + 84b – 60a – 80b = 41 – 40


⇒ 4b = 1



Putting above value in (i),



⇒ 3a = 2 – 1


⇒ 3a = 1





Squaring both the sides,


x = 9


Similarly,


Squaring both the sides,


y = 16


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