1972 AHSME Problems/Problem 30
Problem 30
A rectangular piece of paper 6 inches wide is folded as in the diagram so that one corner touches the opposite side. The length in inches of the crease L in terms of angle is
Solution
Let the rectangle
have crease
with
on
, and let
be on
such that
is a reflection of
over
. Notice that triangles
and
are similar, so by setting
with
, giving
we have that
. Noticing that
:
, not
, so the solution goes off rails here.
gives
.
. Noticing that
gives the answer to be
which is not in the answer list?
If anyone could correct my solution, please help and thanks!
P.S correct answer is .
1972 AHSME (Problems • Answer Key • Resources) | ||
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