How do you solve the following system?: # x=-3y -6, -x-8y=32 #

1 Answer
Dec 3, 2015

This set of equation has one solution:

#{(x=-20 2/5),(y=-4 4/5):}#

Explanation:

#{(x=-3y-6),(-x-8y=32):}#

First I ordered both equations by placing the variables on the left side and free terms on the right side.

#{(x+3y=-6),(-x-8y=32):}#

We can see that variable #x# has opposite coefficients so if I add both equations I get equation with one unknown:

#-5y=24#

#y=-24/5=-4 4/5#

Now I substitute calculated #x# to the first equation:

#x=-3*(-24/5)-6#

#x=-72/5-6#

#x=-72/5-30/5#

#x=-102/5=-20 2/5#