Question

Triangle ABC is similar to triangle PQR.
http://learn.flvs.net/webdav/assessment_images/educator_geometry_v14/pool_Geom_3641_0300_Subtest_04_12/image0064e1c83ed.jpg
Which equation is correct?

q/c is equal to r/b

c/p is equal to b/a

c/a is equal to q/r

q/b is equal to r/c
Give me a sec and I'll show you what I have so far.

Answer 1

AB = PQ
PQ = QR
CA = RP

r = c
p = a
b = q

I think the answer is D.

Answer 2

Uh oh.
These are similar triangles, not congruent ones.

Answer 3

That's not true. I can see it.

Answer 4

facepalm

Answer 5

Okay, so Becca, you've paired the correct sides, but they aren't actually equal. Remember that similar triangles are the same shape, but different sizes.

Answer 6

yeah

Answer 7

Good, so now that you know which sides are corresponding, you can set up an equation about them.

Answer 8

\[\frac{a}{A} = \frac{b}{B}\]
Where a and A are corresponding parts and b and B are corresponding parts.

Answer 9

How are they corresponding on the same triangle?? Sorry if it's a dumb question

Answer 10

I think my variables are what is confusing you. They were just random variables, not related to your problem.

Answer 11

Oh! haha okay

Answer 12

\[\large \frac{\text{\small}}{\text{\big}} = \frac{\text{\small}}{\text{\big}}\]

Answer 13

lol better xD

Answer 14

Or if you prefer, you can do
\[\frac{\text{\big}}{\text{\small}} = \frac{\text{\big}}{\text{\small}}\]

Answer 15

My obsessive compulsive side prefers small on top haha

Answer 16

Mine too :3

Answer 17

I think it's a?
bc
q/c = r/b ? well I think it does anyway

Answer 18

That is big over small and big over small, but the fractions aren't made up of corresponding parts =(

Answer 19

Then C seems to be the only other option bc the other two are not big/small.

Answer 20

@smoothmath help me dollface! xD

Answer 21

I'm going to show you an example. Here is a picture of two similar triangles.


Okay, notice that I've given corresponding sides the same name, but for the bigger triangle, I made that name capital. So a corresponds with A, b corresponds with B, and c corresponds with C. That lets me set up this equality:
\[\large \frac{a}{A} = \frac{b}{B} = \frac{c}{C}\]
There are two important things to check when you write your equality.
1) Each fraction should be made up of two corresponding parts.
2) Always big/small or always small/big. Don't accidentally say something like \[\frac{a}{A} = \frac{B}{b}\]