90 Degree Anticlockwise Rotation

Learn about the rules for 90 degree anticlockwise rotation about the origin.

How do you rotate a figure 90 degrees in anticlockwise direction on a graph?

Rotation of point through 90° about the origin in anticlockwise direction when point M (h, k) is rotated about the origin O through 90° in anticlockwise direction. The new position of point M (h, k) will become M' (-k, h).

90° Anticlockwise Rotation

Worked-out examples on 90° anticlockwise rotation about the origin:

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

(i) A (2, 3)           

(ii) B (-5, -7)       

(iii) C (-6, 9)        

(iv) D (4, -8)

Solution:

When rotated through 90° about the origin in anticlockwise direction. The new positions of the above points are:

(i) The new position of point A (2, 3) will become A' (-3, 2)           

(ii) The new position of point B (-5, -7) will become B' (7, -5)       

(iii) The new position of point C (-6, 9) will become C' (-9, -6)      

(iv) The new position of point D (4, -8) will become D' (8, 4)


2. Draw a triangle ABC on the graph paper. The co-ordinate of A, B and C being A (1, 2), B (3, 1) and C (2, -2), find the new position when the triangle is rotated through 90° anticlockwise about the origin.

Solution:

90 Degree Anticlockwise Rotation

Plot the points A (1, 2), B (3, 1) and C (2, -2) on the graph paper. Join AB, BC and Cato get a triangle. On rotating it through 90° about the origin in anticlockwise direction, the new position of the points are:

A (1, 2) will become A' (-2, 1)

B (3, 1) will become B' (-1, 3)

C (2, -2) will become C' (2, 2)

Thus, the new position of ∆ ABC is ∆ A'B'C'.

Related Concepts

Lines of Symmetry

Point Symmetry

Rotational Symmetry

Order of Rotational Symmetry

Types of Symmetry

Reflection

Reflection of a Point in x-axis

Reflection of a Point in y-axis

Reflection of a point in origin

Rotation

90 Degree Clockwise Rotation

180 Degree Rotation








7th Grade Math Problems

8th Grade Math Practice

From 90 Degree Anticlockwise Rotation to HOME PAGE


New! Comments

Have your say about what you just read! Leave me a comment in the box below. Ask a Question or Answer a Question.



Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.



Share this page: What’s this?

Recent Articles

  1. Adding 5-digit Numbers with Regrouping | 5-digit Addition |Addition

    Mar 18, 24 02:31 PM

    Adding 5-digit Numbers with Regrouping
    We will learn adding 5-digit numbers with regrouping. We have learnt the addition of 4-digit numbers with regrouping and now in the same way we will do addition of 5-digit numbers with regrouping. We…

    Read More

  2. Adding 4-digit Numbers with Regrouping | 4-digit Addition |Addition

    Mar 18, 24 12:19 PM

    Adding 4-digit Numbers with Regrouping
    We will learn adding 4-digit numbers with regrouping. Addition of 4-digit numbers can be done in the same way as we do addition of smaller numbers. We first arrange the numbers one below the other in…

    Read More

  3. Worksheet on Adding 4-digit Numbers without Regrouping | Answers |Math

    Mar 16, 24 05:02 PM

    Missing Digits in Addition
    In worksheet on adding 4-digit numbers without regrouping we will solve the addition of 4-digit numbers without regrouping or without carrying, 4-digit vertical addition, arrange in columns and add an…

    Read More

  4. Adding 4-digit Numbers without Regrouping | 4-digit Addition |Addition

    Mar 15, 24 04:52 PM

    Adding 4-digit Numbers without Regrouping
    We will learn adding 4-digit numbers without regrouping. We first arrange the numbers one below the other in place value columns and then add the digits under each column as shown in the following exa…

    Read More

  5. Addition of Three 3-Digit Numbers | With and With out Regrouping |Math

    Mar 15, 24 04:33 PM

    Addition of Three 3-Digit Numbers Without Regrouping
    Without regrouping: Adding three 3-digit numbers is same as adding two 3-digit numbers.

    Read More