How do you solve #3x+y=3# and #x+2y=-4#?

1 Answer
Aug 14, 2015

Answer:

The solutions for the equation are
#color(blue)(x=2,y=-3#

Explanation:

#color(blue)(3x)+y=3 #.................. equation #(1)#

#x+2y=−4 #, multiplying this equation by #3#
#color(blue)(3x)+6y=−12 #....... equation #(2)#

Now we can solve through elimination as term #color(blue)(3x)# is common to both equations.

Subtracting equation #(2)# from #(1)#
#cancel(color(blue)(3x))+y=3 #
#-cancel(color(blue)(3x))-6y=+12#

#-5y=15#
#color(blue)(y=-3#

Substituting the value of #y# in equation #1#
#x+2y=−4 #
#x+2 * (-3)=−4 #
#x-6=−4 #
#color(blue)(x=2#