#(2x+y)+(3x-4y)i=(x-2)+(4y-5)i# Find x and y..?

1 Answer
May 12, 2018

#x=-21/11,y=-1/11#

Explanation:

We have

#(2x+y)+(3x-4y)i=(x-2)+(4y-5)i#

We know two complex numbers #a+bi# and #c+di# iff #a=c# and #b=d#. So, in this case, we must have

#2x+y=x-2#

#3x-4y=4y-5#

so

#x=-y-2#

#3(-y-2)-4y=-3y-6-4y=-7y-6=4y-5#

so #11y=-1# and #y=-1/11#

Hence, #x=1/11-2=1/11-22/11=-21/11#

We make a quick check:

#2(-21/11)-1/11=-43/11#

#-21/11-2=-21/11-22/11=-43/11#

So, our values of #x# and #y# are correct.