Algebra 2 question. which complex number lies in the shaded triangle in this graph?

The complex number are formed by a real part and an imaginary part.

The imaginary part is indicated with the letter i.

2i is only imaginary, so it is not complex

i - 1 is complex but is out of the triangle.

1 - i indeed is complex and is inside the triangle

2 - 3i is complex but is out of the triangle.

So, the answer is 1 - i