What is the solution set for -9x + 3y = -9 and 3x +4y = -9?

1 Answer
Aug 22, 2015

Answer:

The solutions are
#color(blue)(x=1/5, y=-12/5#

Explanation:

#-color(blue)(9x) + 3y = -9 #.....equation #1#

# 3x +4y = -9#, multiplying by #3#
#color(blue)(9x) +12y = -27#.....equation #2#

Solving by elimination
Adding equations #1# and #2#
#-cancelcolor(blue)(9x) + 3y = -9 #
#cancelcolor(blue)(9x) +12y = -27#

#15y=-36#
#color(blue)(y=-12/5#

Finding #x# from equation #2#
# 3x +4y = -9#

# 3x = -9-4y#

# x = (-9-4y)/3#

# x = 3/15#

#color(blue)(x=1/5#