Question

triangle pqr is reflected over a vertical line of reflection to create triangle pqr. what are the coordinates of point r? (1 point) (11, 1) (-3, 1) (-2, 7) (1, -3)

Explanation:

Step1: Identify line of reflection

The line of reflection is $x = - 7$.

Step2: Use reflection formula

For a point $(x,y)$ reflected over the vertical line $x = a$, the new $x$-coordinate is $2a - x$ and the $y$-coordinate remains the same. Here $a=-7$ and the point $R$ has coordinates $(-11,1)$. The new $x$-coordinate is $2\times(-7)-(-11)=-14 + 11=-3$, and the $y$-coordinate is $1$.

Answer:

$(-3,1)$