ar
en’t r
ight tr
iangles.
triangle properties
Q:
What if I’ve got a triangle which doesn’t have a horizonal
side? How do I draw a bounding rectangle?
A:Use a vertical side if you have one because it does make
things easier, but if you don’t have one, then any side will do.
These ar
e
both fine.
Q:
We’ve talked about sides and angles being the same
in congruent triangles, but how do you know that congruent
triangles have the same area, too?
A:With a bit of flipping and rotation you can always place
congruent triangles on top of one another, and they fit perfectly—so
they must have the same area.
Q:
What if I don’t know the size of the bounding rectangle?
A: Good point. We’re going to cover some ways to find that out.
For RIGHT triangles, this
half-the-rectangle thing
looks sensible. But what
about non-right triangles?
Good question—two of our
fields are not right triangles.
So what can we do?
A
B
C
T
hese t
w
o fi
elds
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