Question

The figure below shows CB = 8, BE = 12, AB = 3x – 1, and DB = 4x + 2.
If ΔABC ~ ΔDBE, the value of x is _________

Answer 1

If the 2 triangles are similar, then the corresponding sides of ABC will be proportional to the corresponding sides of DBE. Do you understand this? If so, I will proceed.

Answer 2

Yeah i understand, i kept doing 4x+2 = 3x-1but the answer i kept getting wasn't making any sense

Answer 3

That's not the correct method. Do you agree that CB corresponds to BE?

Answer 4

Yes i agree

Answer 5

so that means they equal each other, correct?

Answer 6

no. the question statesAB=8 and BE=12. so make a proportion from the bigger to the smaller--12/8=3/2. Now all sides will corresponding side will be in the same proortion

Answer 7

*proportion

Answer 8

Okay, so the ratio is 3/2 ? how does that fit in the problem?

Answer 9

you were trying 3x-1=4x+2 but that is not right.

It should be (4x+2) /(3x-1)=3/2 in order to put these sides in the proper proportion 3/2

Answer 10

then cross multiply and solve

Answer 11

wait like 4x+2 divided by 3x-1?

Answer 12

i get the 3/2, but what am i cross multiplying it with?

Answer 13

(4x+2)/(3x-1)= 3/2--------->2(4x+2)=3(3x-1)

Answer 14

a/b=c/d------------>ad=bc

Answer 15

so X=7?

Answer 16

yes

Answer 17

Thanks :)

Answer 18

ok