Which complex number will be located above the real axis and to the left of the imaginary axis?

a)4i
b)2-4i
c) 4i-1
d) -1-2i

Question

Which complex number will be located above the real axis and to the left of the imaginary axis?

a)4i
b)2-4i
c) 4i-1
d) -1-2i

anonymous · Answer

It will be above the real axis if the coefficient of the $i$ term (i.e. the imaginary part) is positive.  Furthermore, it will be to the left of the imaginary axis if the real part (the number not multiplied by $i$) is negative.  Now, which of those complex numbers has a positive imaginary part AND a negative real part? :-)

anonymous · Answer

That is, we want $a+bi$ so that $a<0$ and $b>0$.  Which of those four choices is of this form?

chosenmatt · Answer

IKR

anonymous · Answer

above real axis = positive real number
to left of imaginary axis = negative complex part