How do solve the following linear system?: # 4x+2y=6 , 3x + y = -20 #?

1 Answer
May 22, 2016

Answer:

The solution for the system of equations is:

#color(green)(x = -23#

# color(green)(y =49 #

Explanation:

#4x + color(blue)(2y) = 6#..............equation #(1)#
#3x + y =- 20#, multiplying by #2#

#6x + color(blue)( 2y) =- 40#......equation #(2)#

Solving by elimination:

Subtracting equation #2# from equation #1#:

#4x + cancelcolor(blue)(2y) = 6#

#-6x - cancelcolor(blue)( 2y) =40#

#-2x = 46 #

#x = 46 /(-2) #

#color(green)(x = -23#

Finding #y# from equation #2:#
#3x + y =- 20#

# y =- 20 - 3x #

# y =- 20 - 3 xx (-23) #

# y =- 20 + 69 #

# color(green)(y =49 #