Question

If x= -5+6i and y= 3-2x, then which of the following is the value of the expression 4x-y

Answer 1

$y=3-2x\\\\4x-y=4x-(3-2x)=4x-3+2x=6x-3\\\\\text{Put}\ x=-5+6i\ \text{to the expression}\ 6x-3:\\\\6(-5+6i)-3\qquad\text{use distributive property}\\\\=(6)(-5)+(6)(6i)\\\\=-30+36i\\\\Answer:\ \boxed{4x-y=-30+36i}$