How do you solve the system of equations $-x - 7y = 11$ and $-2x - 7y = 8$ ?

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Answer 1 · 2017-06-29T03:17:45

The answer is x = 3 and y = -2 .

We have the given equations:

$-x -7y =11$ ..................... (i)
$-2x-7y =8$ ...................... (ii)

Subtracting equation (ii) from equation (i) i.e.

$-x -7y -(-2x-7y) = 11 - 8$

or $-x -7y+2x+7y = 3$
or $x = 3$

Putting x = 3 in equation (i) We get,
$-3 -7y =11$
or $-7y = 11+3$
or $-7y = 14$

Dividing both sides by $-7$
or $-7y/(-7) = 14/(-7)$
or $y = -2$

Therefore $x = 3 and y = -2$

How do you solve the system of equations -x - 7y = 11-x - 7y = 11 and -2x - 7y = 8-2x - 7y = 8?