Reflect over any line and rotate about a point, with coordinate rules

Answer Key - Grade 10 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. Read this first

   Use this

   Coordinate grid, all four quadrants, each square one unit, origin in the middle. Triangle CDF is drawn with its corners labeled and the mirror line x = 2 drawn dashed across the grid; the image is not drawn.

2. 1.

   Triangle CDF on Ari's quilt design has corners C(1, 5), D(-4, 3) and F(3, -2). It flips across the line x = 2. Where is D′? Write it like (7, -3).

   (8, 3)
3. 2.

   Triangle CDF on Jun's map design has corners C(-5, 1), D(2, 3) and F(0, -2). It flips across the line y = 4. Where is C′? Write it like (7, -3).

   (-5, 7)
4. 3.

   Triangle CDF on Kira's crown design has corners C(1, 3), D(-4, 6) and F(2, -5). It flips across the line y = x. Where is D′? Write it like (7, -3).

   (6, -4)
5. 4.

   Triangle FGH on Luz's tent design has corners F(5, 2), G(-3, 4) and H(-6, -1). It flips across the line y = -x. Where is F′? Write it like (7, -3).

   (-2, -5)
6. 5.

   Triangle QSU on Milo's window design has corners Q(-2, -5), S(7, -3) and U(3, 6). It flips across the line y = x. Where is S′? Write it like (7, -3).

   (-3, 7)
7. 6.

   Triangle CDF on Noah's star design has corners C(-6, 1), D(3, -4) and F(4, 5). It flips across the line y = -x. Where is C′? Write it like (7, -3).

   (-1, 6)
8. 7.

   A flip sends Ren's bike marker from P(2, -5) to P′(2, 3). The mirror line is horizontal (y = k). What is k?

   -1
9. 8.

   A flip sends Tala's leaf marker from P(-7, 1) to P′(-1, 1). The mirror line is vertical (x = k). What is k?

   -4
10. 9.

    A flip sends Zee's paper marker from P(6, -2) to P′(6, 8). The mirror line is horizontal (y = k). What is k?

    3
11. 10.

    Jun's bus marker P(3, 6) is flipped across the line y = -2 to P′. How many units long is segment PP′?

    16 units