Question

Solve the following pair of linear equations by the substitution method

x + y = 14 

x – y = 4

Answer 1

x + y = 14 (1)

x - y = 4 (2)

From (1), we obtain

x = 14 - y (3)

Substituting this value in equation (2), we obtain

(14 - y) - y = 4

14 - 2y = 4

10 = 2y

y = 5  (4)

Substituting this in equation (3), we obtain

x  = 9  

∴ x = 9, y = 5