Question

triangle pqr has coordinates p(-1, 5), q(1, 2), and r(-3, -1). determine the coordinates of the vertices of the image after a reflection in the y - axis.
a) p(1, -5), q(-1, -2), and r(3, 1)
b) p(5, -1), q(2, -1), and r(-1, -3)
c) p(1, 5), q(-1, 2), and r(3, -1)
d) p(1, 5), q(1, 2), and r(3, 1)

Explanation:

Step1: Recall reflection rule

When reflecting a point $(x,y)$ over the $y -$axis, the rule is $(x,y)\to(-x,y)$.

Step2: Apply rule to point P

For point $P(-1,5)$, after reflection over the $y -$axis, $x=- 1$ becomes $x = 1$ and $y = 5$ remains the same. So the new $P$ is $(1,5)$.

Step3: Apply rule to point Q

For point $Q(1,2)$, after reflection over the $y -$axis, $x = 1$ becomes $x=-1$ and $y = 2$ remains the same. So the new $Q$ is $(-1,2)$.

Step4: Apply rule to point R

For point $R(-3,-1)$, after reflection over the $y -$axis, $x=-3$ becomes $x = 3$ and $y=-1$ remains the same. So the new $R$ is $(3,-1)$.

Answer:

C. $P(1,5), Q(-1,2), R(3,-1)$