How do you solve the following system: #3x+y=8, x-2y=4 #?

1 Answer
Jan 18, 2016

Answer:

The solution for the system of equations is
#color(blue)(x=20/7 , y=-4/7#

Explanation:

#color(blue)(3x)+y=8#........equation #(1)#

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

Solving by elimination.

Subtracting equation #2# from #1#:
#cancelcolor(blue)(3x)+y=8#
#-cancelcolor(blue)(3x)+6y=-12#

#7y=-4#
#color(blue)(y=-4/7#

Finding #x# from equation #2#

#x-2y=4#

#x=4+2y#

#x=4+2 xx (-4/7)#

#x=4+(-8/7)#

#x=28/7+(-8/7)#

#color(blue)(x=20/7#