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Question
Solve the following pair of linear equations by the substitution method.
s – t = 3
`s/3 + t/2 = 6`
Solution
s – t = 3 ...(1)
`s/3 + t/2 = 6`
From (1), we obtain
s = t + 3 ...(3)
Substituting this value in equation (2), we obtain
`(t + 3)/3 + t/2 = 6`
2(3 + t) + 3(t) = 6 × 6
6 + 2t + 3t = 36
5t = 30
`t = 30/5`
t = 6
Substituting in equation t = 6(3), we obtain
s = 3 + 6
s = 9
∴ s = 9, t = 6
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