How do you solve the system of equations: 3x - 4y = -30, 3x+2y=6?

1 Answer
Aug 14, 2015

Answer:

The solutions for the equations are
#color(blue)(x=-2,y=6#

Explanation:

#color(blue)(3x) - 4y = -30#.....equation #1#
#color(blue)( 3x)+2y=6#.............equation #2#

Solving by elimination.

Subtracting equation #2# from #1# results in elimination of #color(blue)(3x#
#cancel(color(blue)(3x)) - 4y = -30#
#-cancel(color(blue)( 3x))-2y=-6#

#-6y=-36#
#color(blue)(y=6#

Now we find #x# by substituting #y# in equation #1#
#3x - 4y = -30#
#3x = -30+4y#
#3x = -30+4*6#
#3x = -30+24#
#3x=-6#
#color(blue)(x=-2#