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## #1 2020-08-31 15:54:07

johnny453
Guest

### help please im confused

1. A = 2, 6, 8, 9 B = 4, 12, 16, 18

A. prop, s.f.= 1:4
B. prop, s.f.= 1:9
C. prop, s.f.= 1:5
D. prop, s.f.= 1:2
E. prop, s.f.= 1:10
F. prop, s.f.= 1:3
2. A = 2, 3, 6, 10 B= 6, 9, 18, 30

A. prop, s.f.=1:9
B. prop, s.f.=1:3
C. prop, s.f.=1:16
D. prop, s.f.=1:2
E. prop, s.f.= 1:18
F. prop, s.f.= 1:6
3. A = 7, 10, 14, 15 B = 17.5, 25, 35, 37.5

A. Prop, s.f. = 1:9
B. Prop, s.f. = 3:8
C. Prop, s.f. = 2:7
D. Prop, s.f. = 4:9
E. Prop, s.f. = 6:7
F. Prop, s.f. = 2:5
4. A = 4, 4, 5, 6 B = 1.2, 1.2, 1.5, 1.8

A. Prop, s.f. = 6:4
B. Prop, s.f. = 9:2
C. Prop, s.f. = 1:10
D. Prop, s.f. = 11:9
E. Prop, s.f. = 10:3
F. Prop, s.f. = 5:2
5. A = 9, 10, 16, 19 B = 41.4, 46, 73.6, 87.4

A. Prop, s.f. = 0.217
B. Prop, s.f. = 0.318
C. Prop, s.f. = 0.421
D. Not prop
E. Prop, s.f. = 0.294
F. Prop, s.f. = 0.721
6. A = 4, 9, 10, 14 B = 4.8, 10.8, 12, 16.8

A. Prop, s.f. = 0.227
B. Prop, s.f. = 0.756
C. Prop, s.f. = 0.841
D. Prop, s.f. = 0.621
E. Prop, s.f. = 0.124
F. Prop: s.f. = 0.833
7. A = 7, 7, 21, 23 B = 28.7, 28.7, 86.1, 94.3

A. Prop, s.f. = 0.244
B. Prop, s.f. = 0.215
C. Prop, s.f. = 0.284
D. Prop, s.f. = 0.297
E. Prop, s.f. = 0.236
F. Prop, s.f. = 0.212
8. A = 11, 11, 16, 19 B = 16.5, 16.5, 24, 28.5

A. Prop, s.f. = 4:7
B. Prop, s.f. = 2:3
C. Prop, s.f. = 3:9
D. Not prop
E. Prop, s.f. = 4:5
F. Prop, s.f. = 7:1
9. A = 4.4, 8.1, 20.1, 24.1 B = 15.4, 28.35, 70.35, 84.35

A. Prop, s.f. = 2:3
B. Prop, s.f. = 1:2
C. Prop, s.f. = 10:4
D. Prop, s.f. = 2:7
E. Prop, s.f. = 6:10
F. Prop, s.f. = 4:8
10. A = 1.2, 4.9, 18.6, 21.6 B = 0.24, .098, 3.72, 0.98

A. Prop, s.f. = 2:3
B. Prop, s.f. = 1:2
C. Prop, s.f. = 7:4
D. Not prop
E. Prop, s.f. = 7:8
F. Prop, s.f. = 10:2
With this next set of problems, I will give you the first polygon and the scale factor, you find the similar polygon, just like example 2 and 4.

11. A = 2, 3, 7, 10
SCALE FACTOR = 2

A. 6, 9 ,12, 15
B. 2, 5, 10, 12
C. 4, 6, 14, 20
D. 1, 5, 8, 15
E. 9, 10, 14, 25
F. 4, 8, 18, 23
12. A = 2, 5, 6, 9
SCALE FACTOR = 3

A. 8, 10, 22, 34
B. 3, 8, 15, 29
C. 7, 12, 16, 22
D. 6, 15, 18, 27
E. 2, 15, 18, 30
F. 18, 20, 29, 34
13. A = 5, 10, 13, 15
SCALE FACTOR = 0.5

A. 3.4, 8, 10.1, 20
B. 6, 7.2, 12.1, 18
C. 2.5, 5, 8, 11
D. 4, 5.5, 6.6, 10
E. 2.5, 5, 6.5, 7.5
F. 7.5, 9, 10.9, 16.7
14. A = 4, 5, 6, 15
SCALE FACTOR = 1.5

A. 4, 8.7, 11.2, 22
B. 5, 7.3, 9.1, 15
C. 8, 9.2, 15, 17.1
D. 6, 7.5, 9, 22.5
E. 7.4, 5, 8.3, 9.1
F. 9.9, 12, 18.2, 25
15. A = 2, 5, 16, 19
SCALE FACTOR = 2.9

A. 2.3, 5.5, 7.9, 9.5
B. 6.4, 9.2, 11.4, 25.2
C. 6, 7.8, 9.2, 13.5
D. 19, 26.8, 37, 42.5
E. 5.8, 14.5, 46.4, 55.1
F. 14, 17.4, 22.4, 32.9
16. A = 4, 5, 8, 16
SCALE FACTOR = 4.5

A. 18, 22.5, 36, 72
B. 10.4, 18, 29.2, 34
C. 5.2, 9.6, 10, 19.2
D. 3.5, 9, 15.4, 29
E. 16, 19.3, 26, 28
F. 20.2, 26, 29.9, 37.2
17. A = 1, 8, 18, 19
SCALE FACTOR = 2.8

A. 13, 19.6, 23.3, 36
B. 2.9, 9.9, 25.2, 48.7
C. 14, 18.8, 24.2, 38.8
D. 5, 9.2, 10, 13.4
E. 7.4, 8.9, 13.2, 19.1
F. 2.8, 22.4, 50.4, 53.2
18. A = 2, 3, 9, 14
SCALE FACTOR = 3.9

A. 2.4, 5.6, 7.8, 10.9
B. 9.2, 13.1, 27, 31.1
C. 6.4, 9.2, 18, 22.4
D. 7.8, 11.7, 35.1, 54.6
E. 4.7, 8.2, 12.5, 24.2
F. 3.9, 7.5, 10.2, 26.1
19. A = 0.7, 3.6, 7.7, 8
SCALE FACTOR = 2.6

A. 1.99, 9.26, 13.57 26.02
B. 2.91, 6.25, 7.18, 9.29
C. 6.75, 9.21, 10.01, 18.45
D. 3.74, 9.28, 40.05, 44.21
E. 1.82, 9.36, 20.02, 20.8
F. 5.29, 6.82, 9.71, 15.90
20. A = 8.2, 14.5, 15, 18.5
SCALE FACTOR = 4.6

A. 15, 26.1, 38.17, 41.07
B. 42.50, 65.98, 71.35, 75
C. 66.1, 72.8, 79, 86.04
D. 37.72, 66.7, 69, 85.1
E. 10, 14.27, 19, 27.3
F. 22.1, 27, 32.15, 40.05

## #2 2020-08-31 19:54:05

Bob
Administrator
Registered: 2010-06-20
Posts: 9,228

### Re: help please im confused

hi johnny453

Welcome to the forum.

No diagrams?  And no explanation of what this is about.  Sorry but it'll be tough to help under the circumstances.

I'm going to assume this is an exercise on enlargements and scale factors.  Here's an example of a quadrilateral that has been enlarged with a scale factor of x2.

AB is 4cm long and CD is 8cm long.  The other lengths have doubled in size similarly.

If you don't know the scale factor you can work it out like this:

I not sure what 'prop' means in these questions.  In Q8 one possible answer is not prop, so I'm guessing that some questions are deliberately not proper enlargements.  How can you tell?

You have to check every enlarged length.  If the sf is always the same then you can safely conclude that you have a proper enlargement with that sf.  If some sf answers come out differently from others, then that question is not a proper enlargement.

Hope that helps,

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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