If ABC~STO, what is the length of BC?

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Question

If ABC~STO, what is the length of BC?

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anonymous · Answer

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anonymous · Answer

similar triangles means they have proportional sides...
solve the proportion according to "between the triangles" correspondence:

$\large \frac{33}{18}=\frac{x}{21} $

anonymous · Answer

So would I multiply 33 by 21 to get 693 and 18 by x 18x then what? Sorry if this is wrong I'm bad at this and a little confused lol

anonymous · Answer

@agent0smith Can you help me with this?

anonymous · Answer

@agent0smith Any chance you know this?

anonymous · Answer

@Chelsea04 Can you help?

anonymous · Answer

so these triangles as proportionate, that means that there are corresponding sides

anonymous · Answer

so, 33 is the larger (one) of 18.

anonymous · Answer

and BC is the larger one of 12.

anonymous · Answer

so using ratios 33/18=BC/12

anonymous · Answer

$$33/18=BC/12$$
so cross multiply
BC x 18 = 33 x 12

anonymous · Answer

33x12= 693
BCx18 = ?

anonymous · Answer

if BC x 18 = 33 x 12
then BC x 18 = 693
then BC = 693/18

anonymous · Answer

That comes up to 38.5 does that sound right?

anonymous · Answer

yea, sounds right

anonymous · Answer

I don't think that's it lol but I don't know

anonymous · Answer

just wait...

anonymous · Answer

used a calculator and got 22

anonymous · Answer

found it! 33 x 12 = 396, not 693

anonymous · Answer

Oh wow I must of typed it in wrong lol yea its 22 lol

anonymous · Answer

happy with that answer?

anonymous · Answer

Thanks for the help much appreciated!

anonymous · Answer

no problem :)