How do solve the following linear system?: #-3x + 7y= -16 , x - 3y = -6 #?

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Answer 1 · 2018-05-16T13:51:56

#x=45#, #y=17#

From the second equation, you have #x = 3y-6#. Substitute this expression for #x# in the first equation to get

#-3x+7y=-16#

#\therefore -3(3y-6)+7y=-16#

#\therefore -9y+18+7y=-16#

#\therefore -2y=-34#

#\therefore y=17#

Once #y# is known, we can derive #x#:

#x = 3y-6 \implies x = 3*17-6 = 51-6 = 45#