How do you solve 3x+y=3 and 2x+3y=-5?

1 Answer
Sep 5, 2015

The solution is
#color(blue)(x=2,y=-3#

Explanation:

# 3x+y=3 #, multiplying the equation by #3#
# 9x+color(blue)(3y)=9 #........equation #1#

# 2x+color(blue)(3y)=-5#....equation #2#

Solving by elimination as subtracting the two equations eliminates #color(blue)(3y#

Subtracting equation #2# from #1#
# 9x+cancelcolor(blue)(3y)=9 #

#- 2x-cancelcolor(blue)(3y)=+5#

#7x=14#
#color(blue)(x=2#

Finding #y# by substituting #x# in equation #1#
# 3x+y=3 #
# y=3-3x #
# y=3-3*2 #
# y=3-6 #
#color(blue)(y=-3#