Polar equations and their graphs

Answer Key - Grade 11 Math Worksheet - Building Confidence

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

1. 1.

   Esme plots the polar point (4, 90°): turn 90° counterclockwise, then walk r = 4. Which (x, y) point is it?

   • (0, -4)
   • (0, 4)
   • (4, 0)
   • (4, 90)
2. 2.

   Jun plots the polar point (-3, 180°): turn 180° counterclockwise, then walk r = -3. Which (x, y) point is it?

   • (3, 0)
   • (0, 3)
   • (-3, 180)
   • (-3, 0)
3. 3.

   Kira plots the polar point (5, 270°): turn 270° counterclockwise, then walk r = 5. Which (x, y) point is it?

   • (-5, 0)
   • (0, -5)
   • (5, 270)
   • (0, 5)
4. 4.

   Luz plots the polar point (-2, 90°): turn 90° counterclockwise, then walk r = -2. Which (x, y) point is it?

   • (0, 2)
   • (0, -2)
   • (-2, 90)
   • (-2, 0)
5. 5.

   Milo makes a table of points for r = 5 + 3 cos θ. What is r when θ = 180°?

   2
6. 6.

   Noah makes a table of points for r = 1 + 4 cos θ. What is r when θ = 120°?

   -1
7. 7.

   Tala makes a table of points for r = 8 cos 3θ. What is r when θ = 60°?

   -8
8. 8.

   Zee makes a table of points for r = 12 cos 2θ. What is r when θ = 60°?

   -6
9. 9.

   Esme makes a table of points for r = 6 cos 2θ. What is r when θ = 90°?

   -6
10. 10.

    Jun graphs r = 8 cos θ, a circle through the pole. What is the radius of the circle?

    4