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in this video cringe discuss similar triangles
nursing a similar triangles
history she other sides are congruent
what that means
is if we have to similar triangles you don't have to be the same size
so for instance in these two triangles
side day
does not equal sidi
they are not the same size
but i think the ratio of two sides their smaller triangle say a to b
that will be equal to the ratio of the corresponding sides
the bigger trying
let's talk about what we mean by corresponding sides
notice workdays
decide a corresponds to the sidi in the bigger triangle
sometimes you'll see this medication
corresponds to the
so that means and side b corresponds to be
so there would be
is going to be equal
to do you agree
that's a nice property of similar triangles
there's another way we could set up our proportion
died it small triangle people's big trouble
but it turns out we could actually do
let's say we wanted to do
sightseeing which corresponds to side effects
then i can look at the ratio
lucy over a
that'll be cool to ratio of other corresponding sites
immediately recognize
favor de
or be overtly
schools too
delivery
here's what's important when you're setting these up
notice that day over being
as part of the same triangle
they're both part of a little triangle on the same side being here part of the
big triangle members inside
saying look this way noticed that cnv
are part of the little triangle
indefinite leave are part of the big triangle
so they have to be
matched up horizontally
see their financial vertically or horizontally as part of the same
triangle
i would not have wanted to do this
when i wanted to say
tse overpass
peoples
eat overby
these are not part of the same triangle
that is not a tree statement
selection is set up a similar triangles
now how this works looks duties from the sizes
let's say that any equals too
it be deposed really
and
d
equals six thing they want to know
but is equal to
this is how it set up a this problem
well electric duration of my sides ever be
six
equals
let's set up a over big splash setup d overeat
is equal to
six over
densities in question mark of what we used a very
say acts
we now have a proportionately consult
to solve this proportion i'd like to do cross multiplying which is multiply the
denominator
by the other side
that leaves me with
to pax equals
six times three
which is eighteen
seconded by both sides likes you
and i get that that's what missing side eat
is not
now let's just take a look at the center of the other way make sure we get the
same thing
so i know that side is to inside its corresponding side is these six
i could set that up here but what do you don't have the suspects
over to soces delivery
taken note of that delivered eat
equals
you know usually looking for
imperial so no
he india corresponding sides
notice
script blue glare here this week
notices
that d near part of the same triangle they have to go any of the same
horizontal in vertical
i did vertical so the my question mark which were using tax for
has to go on top
now the site he corresponds to the side b
which is three
we don't think he's crosswalks playing every time we feel a bit of a way of
solving this
because i a six over to you
i can't read that the six divided by two united three
equals exit over three
now i need to get rid of this tree in order to solve so what we're doing that
this multiplying both sides by three
those canceled
and yet once again i get xy cause i know that side he is nine
and we look at a couple differ when setting a proportion
and a couple different ways of solving our portion