How do you solve the system #x+6y=-22# and # -6x-2y=-4# by substitution?

1 Answer
Don't Memorise
Jun 10, 2015

The solution for the system of equations is
# color(red)(x = 2 , y=-4#

Explanation:

#x+6y=-22#
#x=color(red)(-22 - 6y# ..................equation #(1)#
# -6x-2y=-4# ............equation #(2)#

Substituting equation #(1)# in equation #(2)# to find #y#

# -6x-2y=-4#
# -6color(red)((-22 -6y))-2y=-4#
#132 +36y -2y =-4 #
#132 +34y=-4 #
#34y=-136 #
#color(red)(y=-4#

Substituting #y# in equation #1# to find #x#
# x = -22 - 6y#
# x = -22 -6.(-4)#
# x = -22+24#
# color(red)(x = 2#

Related questions
See all questions in Linear Inequalities in Two Variables
Impact of this question
2958 views around the world
You can reuse this answer
Creative Commons License