Question

._.

Answer 1

@nincompoop can you help?

Answer 2

what the : means?

Answer 3

i think that's the proportion thing

Answer 4

Ok, they will be paralel if their sides are proportional to each other, if the left side increased 2 times, the right side must increase 2 times too.

Answer 5

but how do i get my answer? :/

Answer 6

BC/BD=BA/BE
BC/20=BA/15
But BC=BD+DC and BA=BE+EA
Then:
(20+BD)/20=(15+EA)/15
(20+BD)3/4=(15+EA)
15+3BD/4=15+EA
3BC=4EA

Answer 7

i don't get this

Answer 8

3BD, not BC in the end

Answer 9

humm, let me think of another way to explain

Answer 10

what's the right answer? :/

Answer 11

ok, BD*x=BC and BE*y=BA
If the lines are paralel, x must be equal to y
Do you understand this?

Answer 12

yes

Answer 13

Then BD/BC=x=y=BE/BA
BD/BC=BE/BA

Answer 14

Can you understand what I did from here? I substituted BC by BD+DE and the same on the other side.

Answer 15

BC=BD+DC sorry

Answer 16

so 3DC = 4EA, right? how do you i get one of the answer choices from that?

Answer 17

It depends on what the : mean, Im not sure if it is divison or multiplication, because both would be acceptable when you talk about proportionality

Answer 18

but is b or d

Answer 19

alright, thanks :/

Answer 20

i think it means division...

Answer 21

would that narrow it down to one choice?

Answer 22

yes, you get 3/EA=4/DC and the answer would be b

Answer 23

ok, thanks. i'll go with that then