Question

x+y=7, 3x–y=1,Solve the given pairs of linear equations by the method of substitution.

Answer 1

y=4 and x=3............

Answer 2

Solution :

x + y = 7

=> y = 7 - x ----( 1 )

3x - y = 1 ----( 2 )

Substitute y = 7 - x in equation ( 2 ),

we get

3x - ( 7 - x ) = 1

=> 3x - 7 + x = 1

=> 4x = 8

=> x = 8/2

=> x = 4

Put x = 4 in equation ( 1 ), we get

y = 7 - 4

=> y = 3

Therefore ,

( x , y ) = ( 4 , 3 )

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