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Problems
Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1986 AMC 12/AHSME
11
11
Part of
1986 AMC 12/AHSME
Problems
(1)
Line length
Source: AHSME 1986 problem 11
9/30/2011
In
△
A
B
C
\triangle ABC
△
A
BC
,
A
B
=
13
AB = 13
A
B
=
13
,
B
C
=
14
BC = 14
BC
=
14
and
C
A
=
15
CA = 15
C
A
=
15
. Also,
M
M
M
is the midpoint of side
A
B
AB
A
B
and
H
H
H
is the foot of the altitude from
A
A
A
to
B
C
BC
BC
. The length of
H
M
HM
H
M
is[asy] size(200); defaultpen(linewidth(0.7)+fontsize(10)); pair H=origin, A=(0,6), B=(-4,0), C=(5,0), M=B+3.6*dir(B--A); draw(B--C--A--B^^M--H--A^^rightanglemark(A,H,C)); label("
A
A
A
", A, NE); label("
B
B
B
", B, W); label("
C
C
C
", C, E); label("
H
H
H
", H, S); label("
M
M
M
", M, dir(M)); [/asy]
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6.5
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7.5
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<span class='latex-bold'>(A)</span>\ 6\qquad<span class='latex-bold'>(B)</span>\ 6.5\qquad<span class='latex-bold'>(C)</span>\ 7\qquad<span class='latex-bold'>(D)</span>\ 7.5\qquad<span class='latex-bold'>(E)</span>\ 8
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6.5
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7
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7.5
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8
AMC