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Purple Comet Problems
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22
Purple Comet 2016 HS Problem 22
Purple Comet 2016 HS Problem 22
Source:
April 12, 2018
Problem Statement
In
△
A
B
C
\triangle{ABC}
△
A
BC
,
c
o
s
∠
A
=
2
3
cos\angle{A} =\frac{2}{3}
cos
∠
A
=
3
2
,
c
o
s
∠
B
=
1
9
cos\angle{B} =\frac{1}{9}
cos
∠
B
=
9
1
, and
B
C
=
24
BC = 24
BC
=
24
. Find the length
A
C
AC
A
C
.
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