How do you solve the following system using substitution?: #-3x + 3y= 3, -5x + y = 13#

1 Answer
Oct 26, 2015

#x=-3#
#y=-2#

Explanation:

First, isolate #y# in the first equation.

#color(blue)([1])" "-3x+3y=3#

#color(blue)([2])" "3y=3+3x#

#color(blue)([3])" "y=1+x#

Now substitute the value of #y# in the first equation to #y# in the second equation.

#color(red)([1])" "-5x+color(blue)(y)=13#

#color(red)([2])" "-5x+color(blue)((1+x))=13#

#color(red)([3])" "-4x=12#

#color(red)([4])" "x=-3#

Now that we have the value of #x#, we will simply substitute this to the first equation.

#color(blue)([4])" "y=1+(-3)#

#color(blue)([5])" "y=-2#