How do you solve the following system: #-29=5y-3x, 4x-5y= -1 #?

1 Answer
Jan 17, 2018

Solve the former one first
#-29=5y-3x#
Solve for #y#
Transfer #3x#
#3x-29=5y#
You can also transfer the #5# in #5y# but that would be stupid considering that the next equation wants #5y#
The latter equation
#4x-5y=-1#
Put the value of #5y#
#4x-(3x-29)=-1#
Which gives us
#4x-3x+29=-1#
Solve
#x+29=-1#
Transfer the #-1#
#x+29+1=0#
#x+30=0#
Which gives
#x=-30#
#5y=3x-29#
Put value of #x#
#5y=3xx(-30)-29#
Solve
#5y=-90-29#
Solve
#5y=-119#
Transfer #5#
#y=-119/5#
Or...
#y=-23.8#