Question

>>> http://prntscr.com/1z99fy

Curious. I don't understand the ratio. What does 1:3 mean? How did they get it?

Answer 1

@marcoduuuh @robtobey @Compassionate @LaceyLeanne @ganeshie8

Answer 2

1:3

if you have $1 in your pocket and I have $3 in mine
then the difference in ratio is $1 of yours to $3 of mine so 1:3

Answer 3

something is BIGGER than other by that much
when one is 1, the other is 3

say a ratio of 5:9

same thing, when one is 5, the other is 9

Answer 4

like say, what are your chances of winning the superduper lottery today? well, you'd say 1 in a million!! that just means the ratio is 1:1,000,000

Answer 5

what they did in this problem was find the length of the line segments and then compare the smaller to the larger to figure out the ratio

Answer 6

a / b = 2 / 3 is same as saying a:b = 2:3

Answer 7

ohh smokes... man going blind, I haven't checked the picture =)

Answer 8

But how does BR and DB become 1:3? That's what confuses me.

Answer 9

thought it was just a generic inquiry

Answer 10

You have to find the length of BR and the length of DB first.
Then find the lengths of KE and YK.
The do the ratio.

Answer 11

How would you do that?

Answer 12

notice each vertex or point, has a x, y coordinate, so

\(\large {\text{distance between 2 points}\\
d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}}\)

Answer 13

like ranga said, get a couple of segment's length from one, and the same CORRESPONDENT segments from the other, and compare the ratios

Answer 14

That's what I don't understand. What points would I plug into the distance formula?

Answer 15

To find the length of BR, the two points will be B and R.

Answer 16

the bottom line is, you want the line's length, so pick whichever, so long you get the line's length

Answer 17

One way to remember jdoe0001 formula above is: take the difference in x coordinates and square it. Take the difference in y coordinates and square it. Add the two squares and then take the square root to get the distance between the two points.

Answer 18

I remember the formula. I want to know WHAT coordinates I have to plug into the formula..

Answer 19

I will find the length of BR and you can apply the same method for the other three lengths.

B is (5, 6) and R is (6, 4). The distance between B and R (same as saying the length of BR) is: sqrt( (6-5)^2 + (4-6)^2 ) = sqrt( 1 + 4 ) = sqrt(5)

So BR = sqrt(5)

Answer 20

DB = 5, too. Okay. So what's the next step?

Answer 21

You may have to redo DB. Also don't forget the square root.

Answer 22

I got it right.

(5, 1) + (6, - 4)

4^2 + 2^2

16 + 4

20
Take the square root
5.

Answer 23

@mertsj

Answer 24

sqrt(20) is not 5.

Answer 25

@skullpatrol @e.mccormick @e.cociuba @Luigi0210

Answer 26

\(\bf B(5,6)\qquad R(6,4)\\ \quad \\

d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}\implies
d = \sqrt{(6-5)^2 + (4-6)^2}\\ \quad \\
d = \sqrt{1^2+(-2)^2}\implies d = \sqrt{5}\)

Answer 27

\(\bf d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}\implies
d = \sqrt{(5-1)^2 + (6-4)^2}\\ \quad \\
d = \sqrt{4^2+2^2}\implies d = \sqrt{20}\\ \quad \\
\color{blue}{\textit{notice that }\quad 20 = 2\times 2\times 5\implies 2^2\times 5}\\ \quad \\
d = \sqrt{20}\implies d = \sqrt{2^2\times 5}\implies d = 2\sqrt{5}\)

Answer 28

that is \(\bf D(1,4)\qquad B(5,6)\\ \quad \\

d = \sqrt{(x_2-x_1)^2 + (y_2-y_1)^2}\implies
d = \sqrt{(5-1)^2 + (6-4)^2}\\ \quad \\
d = \sqrt{4^2+2^2}\implies d = \sqrt{20}\\ \quad \\
\color{blue}{\textit{notice that }\quad 20 = 2\times 2\times 5\implies 2^2\times 5}\\ \quad \\
d = \sqrt{20}\implies d = \sqrt{2^2\times 5}\implies d = 2\sqrt{5}\)

Answer 29

and then you'd do the same for other 2 points on the bigger figure

Answer 30

I gather the obvious ones will be KE and YK

Answer 31

I understand this part. And thank you! for explainit. But how do I put them in a ratio? That confuses me.