How do you solve the following system: #3x+4y=-10, x-2y=4 #?

1 Answer
Jan 8, 2016

The solution for the system of equations is
#color(blue)(x=-2/5, y=-11/5#

Explanation:

#color(blue)(3x)+4y=-10#......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)+4y=-10#
#-cancelcolor(blue)(3x) +6y=-12#

#10y =-22#

#y =-22/10#

#color(blue)(y =-11/5#

Finding #x # from equation #2#
#x -2y=4#

#x =4 +2y#

#x =4 +2 xx(-11/5)#

#x =4 -22/5#

#x =20/5 -22/5#

#color(blue)(x= -2/5#