x+y=14, x–y=4 solve the pair of linear equations by the substitution method

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 1. Solve the following pair of linear equations by the substitution method.

(i) x+y=14, x–y=4

Solution:

x+y=14--------(1)

x–y=4----------(2)

Let we take equation (1) and make x form

x+y=14

x=14-y--------(3)

Now substitute x in equation (2)

x–y=4

14-y-y=4

14-2y=4

14-4=2y

2y=10

Y=10/2=5

Y=5

Substitute y value in equation (3)

x=14-y

x=14-5=9

x=9, y=5

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