How do you solve the following system: #4x-5y= -1, -2x=6y+18 #?

1 Answer
Dec 31, 2015

Answer:

The solution for the system of equations is
#color(blue)(x=-96/34,y=-35/17#

Explanation:

#color(blue)(4x)-5y=-1#........equation #1#

#-2x-6y=18#, multiplying by #2#
#color(blue)(-4x)-12y=36#........equation #2#

Solving by elimination.
Adding equations #1# and #2#

#color(blue)(cancel4x)-5y=-1#

#color(blue)(cancel(-4x))-12y=36#

#-17y=35#

#color(blue)(y=35/(-17)#

Finding #x# from equation #2#:

#-2x-6y=18#

#-2x=18+6y#

#-2x=18+6 xx (-35/17)#

#-2x=18-210/17#

#-2x=306/17-210/17#

#-2x=96/17#

#x=96/(17xx-2)#

#color(blue)(x=96/(-34)#