How do you solve the following system: #-2x + 5y = 20, 2x – 4y = 8#?

1 Answer
Dec 26, 2015

Answer:

The solution for the system of equations is

#color(blue)(x=60, y=28#

Explanation:

#color(blue)(-2x)+5y=20#.......equation #(1)#

#color(blue)(2x) -4y=8#.............equation #(2)#

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

#cancelcolor(blue)(-2x)+5y=20#
#cancelcolor(blue)(2x) -4y=8#

#color(blue)(y=28#

Finding #x# by substituting #y# in equation #1#

#-2x+5y=20#

#-2x+5 xx color(blue)(28)=20#

#-2x+140=20#

#-2x=20-140#

#-2x=-120#

#x=120/2#

#color(blue)(x=60#