Q1 of 186 Page 3

Solve the following pair of linear equations by substitution method:

x + y = 14


x – y = 4

Given equations are


x + y = 14 …(i)


x – y = 4 …(ii)


From eqn (ii), x = 4 + y …(iii)


On substituting x = 4 + y in eqn (i), we get


⇒ 4 + y + y = 14


⇒ 4 + 2y = 14


⇒ 2y = 14 – 4


⇒ 2y = 10



Now, on putting in eqn (iii), we get


⇒ x = 4 + 5


⇒ x = 9


Thus, x = 9 andy = 5 is the required solution.


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