Question

the point of intersection of the lines X + Y = 1 and x -Y =1 is
option A 0, 1
option b 1, 0
option C 1,1
option d 1,0

Answer 1

add both equation
on adding you'll get
2x=2
x=1
substitute the value of x
x+y=1
1+y=1
y=0
option b and d are correct

Answer 2

Solution :

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

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

Add ( 1 ) and ( 2 ), we get

2x = 2

=> x = 2/2 = 1

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

1 + y = 1

=> y = 1 - 1 = 0

Therefore ,

( x , y ) = ( 1 , 0 )

Option ( b ), and ( d ) are correct.

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