How do you solve the system?: #X+Y= -1, Y=3X-17#

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Answer 1 · 2018-03-02T06:47:04

#X=4, Y=-5#

If we know #Y=3X-17,# we can just go ahead and replace #Y# in #X+Y=-1# with #3X-17#

#X+Y=-1hArrX+3X-17=-1#

Now, we have an equation with one unknown variable, which can be easily solved.

#4X-17=-1#

#4X=-1+17=16#

#X=16/4=4#

We need #Y.# We know #X=4,# so we can plug in #4# for #X# in #X+Y=-1# and solve for #Y:#

#4+Y=-1#

#Y=-1-4=-5#