Question 15 Marks
The points P (1,-1 ), Q ( 4,-1) and R ( 4, 3) are reflected in y-axis. If the images are denoted byP' , Q' , and R' , then
(i) Find the co-ordinates of P'Q'R' , Q' and R'
(ii) What kind of figure is formed by RR' Q' Q?
(iii) Find the perimeter of the figure P'Q'R'
(i) Find the co-ordinates of P'Q'R' , Q' and R'
(ii) What kind of figure is formed by RR' Q' Q?
(iii) Find the perimeter of the figure P'Q'R'
Answer
View full question & answer→(i) Find the co-ordinates of $P^{\prime} Q^{\prime} R^{\prime}, Q^{\prime}$ and $R^{\prime}$
The co-ordinates are: $P^{\prime} Q^{\prime} R^{\prime}=(-1,-1) ; Q^{\prime}=(-4,-1) ; R^{\prime}=(-4,3)$
(ii) What kind of figure is formed by RR' $Q^{\prime} Q^{\text {? }}$
A rectangle is formed by RR' Q' Q.
(iii) Find the perimeter of the figure $P^{\prime} Q^{\prime} R^{\prime}$
The figure is a right angled triangle with sides 4 units, 3 units and 5 units.
Here, height $=4$ units, base $=3$ units and
$\text { Hypotenuse }=\left(\sqrt{4}^2+3^2\right)$
$=\sqrt{16+9}$
$=\sqrt{25}$
$=5 \text { units }$
Perimeter $=$ height + base + hypotenuse
$=4+3+5$
$=12 \text { units }$
The co-ordinates are: $P^{\prime} Q^{\prime} R^{\prime}=(-1,-1) ; Q^{\prime}=(-4,-1) ; R^{\prime}=(-4,3)$
(ii) What kind of figure is formed by RR' $Q^{\prime} Q^{\text {? }}$
A rectangle is formed by RR' Q' Q.
(iii) Find the perimeter of the figure $P^{\prime} Q^{\prime} R^{\prime}$
The figure is a right angled triangle with sides 4 units, 3 units and 5 units.
Here, height $=4$ units, base $=3$ units and
$\text { Hypotenuse }=\left(\sqrt{4}^2+3^2\right)$
$=\sqrt{16+9}$
$=\sqrt{25}$
$=5 \text { units }$
Perimeter $=$ height + base + hypotenuse
$=4+3+5$
$=12 \text { units }$