Question

(x+2i) (y-i)=-4-7i

Answer 1

what do you get when you expand the left hand side of that equation?

Answer 2

xy-xi+2yi-2 OR (xy-2)+(-x+2y)i

Answer 3

very good,

now just compare the real parts and imaginary parts on each side

Answer 4

xy-2=-4 AND -x+2y=-7i

Answer 5

Sorry xy-2=-4 AND -x+2y=-7

Answer 6

That's right

Answer 7

so you now have a system of two equations

Answer 8

Yes, but here is my blackout

Answer 9

solve this second equation -x+2y=-7
for x, then sub that into the first equation

you should get a quadratic for y

Answer 10

Thanks that is why I have two pairs of answers

Answer 11

yep, unfortunately these final answers aren't pretty

Answer 12

See you

Answer 13

whoops i missed something,
in the first step, the expansion
2i times -i should be -2i^2 = -2(-1) = 2, [not -2]

sorry