The correct options are
A (−1,−4)
B (1,−4)
Given : (−3+iyx2) and (x2+y+4i) are conjugates of each other, then
(−3+iyx2)=¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯(x2+y+4i)⇒(−3+iyx2)=x2+y−4i⇒x2+y=−3, x2y=−4
Solving both, we get
(−3−y)y=−4⇒y2+3y−4=0⇒(y+4)(y−1)=0⇒y=−4,1⇒x2=1,−4
As x2≥0, so
x2=1, y=−4∴(x,y)=(1,−4), (−1,−4)