Question

The figure below shows CB = 4, BE = 5, AB = x - 4, and DB = x + 3.

Answer 1

If △ABC ~ △DBE, the value of x is _________

Answer 2

is that similar or congruent?

Answer 3

similar

Answer 4

yeah, i see that like edges are 4 and 5

so, since they are similar they differ my some multiple "m"; such that:

4m = 5 ... what is the value of the multipler?

Answer 5

the like sides to then compare are:

m(x+3) = x-4

Answer 6

hmmmmm
so i divide 5 by 4 correct?

Answer 7

thats 0.8 correct?

Answer 8

or possible the other way around ...

x+3 = m(x-4)

Answer 9

so then 0.8(x+3)=x-4

Answer 10

0.8x + 2.4 = x-4

Answer 11

subtract 2.4 from both sides
and you have 0.8x = x-6.4

Answer 12

@armistre

Answer 13

@armistre64

Answer 14

the "little" triangle is multipled by m to equal the bigger one

m(little) = big

m(x-4) = x+3

i had the triangles backwards at first

Answer 15

mx - 4m = x+3

mx -x = 4m+3

x(m -1) =4m+3

x = (4m+3)/(m-1)

Answer 16

so what is M? 0.8?

Answer 17

since 4m = 5, m = 5/4 is going to be greater than .8

Answer 18

ok so where do I go now? haha

Answer 19

If m is 5/4 then you plug that into what equation?

Answer 20

yes

Answer 21

x = (4m-3)/(m-1)

Answer 22

err.. +3. my fingers hate me

Answer 23

and M is 0.8 or 5/4?

Answer 24

that has already been addressed in the postings .....

Answer 25

so according to your post m = 0.8
So... we plug that in to get.... (giveme a sec)

Answer 26

since 4m = 5, m = 5/4 is going to be greater than .8

Answer 27

so X= 2/0.25?

Answer 28

more like

[4(5/4)+3] / [5/4 - 4/4]

[5+3] / [1/4]

8/ [.25]

Answer 29

oh ok
so I plug that in for X?

Answer 30

yes, that will be the value of x

Answer 31

you might need to reduce it more to be formated correctly

Answer 32

ok and I plug it into what equation?
and I plug it in as 32

Answer 33

since the end goal was to determine a value for x, and we found that x = 32 .... there is nothing left to do with the problem

Answer 34

oh ok thanks so much! i hate final exams lol

Answer 35

youre welcome