Worksheet on 90 Degree Anticlockwise Rotation

Practice the questions given in the worksheet on 90 degree anticlockwise rotation about the origin. The questions are based on how to rotate a shape about the origin 90° counter-clockwise direction and find its new co-ordinates.

1. Find the new position of each of the following points when rotated through 90° anticlockwise about the origin.

(i) P (-5, -7)

(ii) Q (-2, 3)

(iii) R (4, -9)

(iv) S (2, 4)

2. Construct a parallelogram ABCD with its vertices A (-1, 2); B (3, 2); C (0, -1); D (-4, -1) and rotate it about the origin through 90° anticlockwise. Find the co-ordinates of its vertices in the new position.

3. Write the co-ordinates of the points given below when rotated through 90° anticlockwise about the origin.

(i) A (-3, 9)

(ii) B (5, 2)

(iii) C (0, -6)

(iv) D (-3, -9)

4. Plot the point X (-5, -3) on the graph. Find the new position of X when it is rotated through 90° anticlockwise direction about the origin.

5. Draw a rectangle PQRS on the graph paper where the co-ordinates of P, Q, R and S are (5, 4), (7, 4), (7, -3) and (5, 3) respectively. Rotate it about origin through 90° in anticlockwise direction. Find the new position of the rectangle.

6. Plot the points A (-4, -2) and B (-3, 5) on the graph paper. Join AB. Rotate the line segment AB about the origin through 90° in anticlockwise direction and write the co-ordinates of A' and B'.

Answers for the worksheet on 90 degree anticlockwise rotation are given below to check the exact answers of the above questions for finding the new position when the point is rotated through 90° counter-clockwise about the origin.

Answers:

1. (i) P' (7, -5)

(ii) Q' (-3, -2)

(iii) R' (9, 4)

(iv) S' (-4, 2)

2. A' (-2, 1); B' (-2, 3); C' (1, 0); D' (1, -4)

3. (i) A' (-9, -3)

(ii) B' (-2, 5)

(iii) C' (6, 0)

(iv) D' (9, -3)

4. X' (3, -5)

5. P' (-4, 5), Q' (-4, 7), R' (3, 7) and S' (-3, 5)