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 #