How do you solve $x - y = 11$ and $x + y = 1$ using substitution?

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Answer 1 · 2018-04-10T07:56:30

$therefore x = 6 " and " y = -5$

Rearrange first equation

$x-y = 11$

$=> x = 11 + y$

Substitute this into the second equation...

$=> ( 11 + y ) + y = 1$

$=> 11 + 2y = 1$

$=> 2y = -10$

$=>color(red)( y = -5$

We know $x = 11+y$

$=> x = 11 + (-5 )$

$=> color(red)(x = 6$

$color(blue)(therefore x = 6 " and " y = -5$

How do you solve x - y = 11x - y = 11 and x + y = 1x + y = 1 using substitution?