1. TEST TOMORROW: TRANSFORMATIONS and what’s preserved Translation, Rotation(90,180,270), Reflection(y axis, x axis, orgin, y=x and y= -x, Dilation, Compositions Isometry( direct and opposite) THE FOLLOWING ARE SAMPLE QUESTIONS, ANSWERS ARE AT THE END

2. Q1. What is an isometry?

3. Q2. MULTIPLE CHOICE: Which of the following would result in a direct isometry? A.first T 5, -2 then reflected over x-axis B.first T -1, 3 then reflect over line x = 3 C.First T 0, 2 then rotate 90 o counter clockwise

4. Q3. Find the dilation or scale factor k, when (6, 3) is mapped onto (4, 2).

5. Q4: Find the translation occurs when (-1, 3) is mapped onto (2, 2).

6. Q5: Find the Rotation which occurs when (-1, 3) is mapped onto (3,1).

7. Q6. What transformation will map point D onto point E?

8. ANSWER KEY Q1. An isometry is a transformation which preserves distance (or size) Q2. Choice C; Choice A and B contain a single line reflection which would not preserve orientation. Q3. 2 / 3 ; (kx, ky) = (x’, y’) k(6) = 4 or k(3) = 2 k = 4/6 = 2/3 Q4. T 3,-1 ; (x + a, y + b) = (x’, y’) -1 + a = 2and 3 + b = 2 a = 3 b = -1 Q5. R 270 ; (x,y)  (y, -x) Q6. R 180 or r 0,0 or T -8,-6 ; all answers are acceptable as D(4, 3) and E(-4,-3) Q7. Dilation; changes the size therefore changes the area.

9. Q.7 What transformation would change the area of a figure?