Graphs & Transformation (May 2, 2024) 1.pptx

Graphs & Transformation

1. Subject: Mathematics ii Class: VII Topic: Graphs & Transformation Subject Teacher: Suraiya Hossain

2. Graphs & Transformation Day: Thursday Date: 02/05/2024 Classwork: Concept of reflection across an axis will be explained. From handout, Questions- 3(c), example 1 and practice problem 1 of reflection will be done in the class.

3. Graphs & Transformation Problem 3: (c) Graph the equation . Solution: The chart below is the table of values for the equation, .   -2 (0, -2) 1 -4 (1, -4) 2 -6 (2, -6) -2 (0, -2) 1 -4 (1, -4) 2 -6 (2, -6)

4. Graphs & Transformation

5. Graphs & Transformation Reflection: A reflection flips a figure over a line to create a mirror image. Rules for performing a reflection across an axis 1. When reflecting across the y-axis, the y-coordinate remains the same and the x-coordinate changes sign. For example, (2,3) becomes (-2, 3) after reflection through y-axis.

6. Graphs & Transformation 2. When reflecting across the x-axis, the x-coordinate remains the same and the y-coordinate changes sign. For example, (2, 3) becomes (2, -3) after reflection across the x-axis.

7. Graphs & Transformation Example: Graph the image of rectangle JKLM after a reflection over the y-axis.

8. Graphs & Transformation Solution: The coordinates in the rectangle JKLM are: J (-8, -5), K(-2, -5), L(-2, 2) and M(-8, 2). So after reflection across the y-axis, the coordinates of new points will be J’(8, -5), K’(2, -5), L’(2, 2) and M’(8, 2).

9. Graphs & Transformation The answer is: (-2,2) (-8,2) (-8,-5) (-2,-5) (2,2) (8,2) (2,-5) (8,-5)

10. Graphs & Transformation Practice Problem: 1. Graph the image of square DEFG after a reflection over the x-axis.

11. Graphs & Transformation Solution: The coordinates in the square DEFG are: D (-7, 7), E(-5, 7), F(-5, 9) and G(-7, 9). So after reflection across the x-axis, the coordinates of new points will be D’(-7, -7), E’(-5, -7), F’(-5, -9) and G’(-7, -9).

12. Graphs & Transformation (-5,7) (-7,7) (-5,9) (-7,9) (-5,-7) (-7,-7) (-5,-9) (-7,-9)