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प्रश्न
Solve the following pair of linear equations by the substitution method.
x + y = 14
x – y = 4
उत्तर
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
-2y = -10
y = 5 ...(4)
Substituting y = 5 in (3), we have
x = 14 - 5
=> x = 9
Hence, x = 9, y = 5
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