Question

The L-shaped ABCDEF is reflected about $x=-1$ to L-shaped $A^{\prime }{B}^{\prime }{C}^{\prime }{D}^{\prime }{E}^{\prime }{F}^{\prime }$. The mirror images of the points $A(-3,3)\&B(-3,2)$ are & respectively.

• A. $A^{\prime }(1,3)$
• B. $A^{\prime }(2,3)$
• C. $B^{\prime }(1,2)$
• D. $B^{\prime }(2,2)$

Answer 1

Answer: (A), (C)

$B^{\prime }(1,2)$

Given : The L-shaped ABCDEF is reflected about $x=-1$ to L-shaped $A^{\prime }{B}^{\prime }{C}^{\prime }{D}^{\prime }{E}^{\prime }{F}^{\prime }$.
The mirror image of $A$, i.e. $A^{\prime }$, must be at the same distance to the right as $A$ is to the left from the mirror line $x=-1$.
As $A$ is $2$ units left from $x=-1$, $A^{\prime }$ is $2$ units right from $x=-1$.
$A(-3,3)\to A^{\prime }(-3+4,3)=A^{\prime }(1,3)$
Similiarly,
As $B$ is $2$ units left from $x=-1$, $B^{\prime }$ is $2$ units right from $x=-1$.
$B(-3,2)\to B^{\prime }(-3+4,2)=B^{\prime }(1,2)$