Ch 9.1 thru 9.5Review

Standard: various

Learning Target:I will be able to use proportions to determine similarity and parallel line segments of a triangle.

Ch 9.Rev

Ch 9.1

Ch 9.1

Property of Proportions

Theorem 9-1

For any numbers a and c and any nonzero numbers b and d,

if , then ad = bc.

Likewise, if ad = bc, then

ab

cd=

ab

cd=

Ch 9.1

9) x = 49Answers:

10) x = -15

11) x = ± 10 12) x = 4.5

Ch 9.2

Definition of Similar Polygons

Ch 9.2

Theorem 9-10

Ch 9.2

15) not similar 4 10

≠ 6 16

16) PQRS~WXYZ15 9

= 10 6

Ch 9.2

13) 5x + 8x + 10x = 276; x = 12; 10(12) = 120

Answers:

14) 3x + 2x = 12; x = 2 ⅖; 3(2 ⅖) = 7⅕, 2(2 ⅖) = 4 ⅘

Ch 9.2

3 50

= 15 + 10 + 13 x

x = 633 ⅓

Ch 9.3

Postulate 9-1

Ch 9.3

9-2

9-3

Ch 9.3

not similar(shapes arenot the same)

IJK ~ HFGSSS Similarity

not similar(angles are not congruent) TUV ~ TSR

AA Similarity

Ch 9.4

Theorem 9-5

Ch 9.5

Theorem 9-6

Ch 9.4

4 x

= 5 12

x = 9.6

8 18

=10 x

x = 22.5

240 200

=300 x

x = 250

Ch 9.5

Theorem 9-7

Ch 9.5(Justify your answer)

IJ = 10.5

• Since FI = IG, then I is the midpoint.• Since FJ = JH, then J is the midpoint.• By definition, IJ is the midsegment.• By the Triangle Midsegment Theorem, IJ = ½ GH