Question

A point $P(3,-2)$ is reflected in the origin as $P^{\prime }$. Point $Q(-7,1)$ is reflected in the x- axis as $Q^{\prime }$. Write down the co-ordinates of $P^{\prime }$ and $Q^{\prime }$.

• A. $P^{\prime }(-3,2),Q^{\prime }(-7,-1)$
• B. $P^{\prime }(3,-2),Q^{\prime }(-7,1)$
• C. $P^{\prime }(-7,-1),Q^{\prime }(-3,2)$
• D. $P^{\prime }(-3,-7),Q^{\prime }(-3,-1)$

Answer 1

The correct option is A

$P^{\prime }(-3,2),Q^{\prime }(-7,-1)$

When a point is reflected in the origin, the sign of its ordinate and abscissa changes. Hence, the coordinates of $P^{\prime }$ are $(-3,2)$.
When a point is reflected in the x axis, the sign of its ordinate changes. Hence, the coordinates $Q^{\prime }$ are $(-7,-1)$.