For each figure answer the following questions

9514 1404 393

  a) ∆ABC ~ ∆EDC by AA similarity

  b) ED/AB = 3/4

  c) 15 cm

Step-by-step explanation:

a) Two angles in each triangle are the same, so the AA similarity postulate can be used to declare the ∆ABC ~ ∆EDC. (Each triangle includes a right angle and angle C.)

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b) Corresponding sides are ED/AB, DC/BC, EC/AC. The ratio of corresponding sides is ED/BC = (12 cm)/(16 cm) = 3/4.

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c) Using the ratios identified above, we have ...

  DC/BC = 3/4 = x/(20 cm)

  x = 3/4(20 cm)

  x = 15 cm

took the test it's 94

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional