Mathematics
Solve the following pair of linear equations by the substitution method.
x + y = 14 and x - y = 4
Answer
Given,
x + y = 14 …….(1)
x - y = 4 ……..(2)
Solving equation (1),
⇒ x + y = 14
⇒ y = 14 - x ………..(3)
Substituting above value of y in x - y = 4, we get :
⇒ x - (14 - x) = 4
⇒ x - 14 + x = 4
⇒ 2x = 4 + 14
⇒ 2x = 18
⇒ x = 9.
Substituting value of x in equation (3), we get :
⇒ y = 14 - 9 = 5.
Hence, x = 9 and y = 5.
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