Question

State the co-ordinates of the images of the following points under reflection in the $y$-axis:

(ii) $(-1,-3)$

Answer 1

Given point: $(-1,-3)$

Reflection in the $y$-axis,$M_y(x,y)=(-x,y)$

$\Rightarrow M_y(-1,-3)=(1,-3)$

$\therefore$The co-ordinates of the image of the given point under reflection in the $y$-axis are $(1,-3)$.