Q2 of 71 Page 68

Draw the graphs of the pair of linear equations in two variables. x + 3y = 6, 2x — y = 5. Find its solution set.

For drawing the given pair of linear equations we need few coordinates to plot of these equations.



In x + 3y = 6,


If x = 0 then 0 + 3y = 6


⇒ y = 2


B(0, 2)


If y = 0 then x + 0 = 6


⇒ x = 6


D(6, 0)


In 2x — y = 5,


If x = 0 then 0 – y = 5


⇒ y = – 5


C(0, – 5)


If y = 0 then 2x + 0 = 5


⇒ x = 2.5


E(2.5, 0)


Now plot B, C, D and E on graph,



We find that A(3, 1) is the intersecting point of the lines. Hence, {(3, 1)} is the solution set of the pair of linear equations.


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