Q1 of 186 Page 3

Solve the following pair of linear equations by substitution method:

7x— 15y = 2


x + 2y = 3

Given equations are


7x – 15y = 2 …(i)


x + 2y = 3 …(ii)


From eqn (ii), x = 3 – 2y …(iii)


On substituting x = 3 – 2y in eqn (i), we get


⇒ 7(3 – 2y) – 15y = 2


⇒ 21 – 14y – 15y = 2


⇒ 21 – 29y = 2


⇒ – 29y = – 19



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






Thus, and is the required solution.


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