Triangle ABC is similar to triangle EBD. y
6
5
A
4
3
2
1
B
-6-5-4-3-2-1 1 2 3 4 5 6
NE
ED
-4
-5
-6+
which two transformations performed on triangle ABC and its image will prove triangle ABC and triangle EBD are similar?
dilation centered about the origin, with a scale factor of
A rotation of 90° clockwise about the origin
D.
2
B. rotation of 90° counter-clockwise about the origin
dilation centered about the origin, with a scale factor of
2
C. rotation of 270° clockwise about point C
F. dilation centered about point C. with a scale factor of 2

Each of the following data sets has a mean of x = 10. (i) 8 9 10 11 12 (ii) 7 9 10 11 13 (iii) 7 8 10 12 13 (a) without doing any computations, order the data sets according to increasing value of standard deviations. (i), (iii), (ii) (ii), (i), (iii) (iii), (i), (ii) (iii), (ii), (i) (i), (ii), (iii) (ii), (iii), (i) (b) why do you expect the difference in standard deviations between data sets (i) and (ii) to be greater than the difference in standard deviations between data sets (ii) and (iii)? hint: consider how much the data in the respective sets differ from the mean. the data change between data sets (i) and (ii) increased the squared difference îł(x - x)2 by more than data sets (ii) and (iii). the data change between data sets (ii) and (iii) increased the squared difference îł(x - x)2 by more than data sets (i) and (ii). the data change between data sets (i) and (ii) decreased the squared difference îł(x - x)2 by more than data sets (ii) and (iii). none of the above