Answer:
F. 8
Step-by-step explanation:
The ratio of the long side to the short side is the same in similar triangles. The long side of triangle BAD is AD, which has length 20-4 = 16.
BD/DE = AD/BD
h/4 = 16/h
h^2 = 64 . . . . . . . multiply by 4h
h = 8 . . . . . . . . . . take the square root (matches selection F)
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<em>Comment on this geometry</em>
BD = √(AD·DC) is called the "geometric mean" of the segments AD and DC. This geometry has some other geometric mean relationships as well:
BC = √(AC·DC)
BA = √(AC·AD)
It will expand. Or it will grow.
K is the right answer for the problem!
(A)
P(<em>X</em> < 61.25) = P((<em>X</em> - 55.4)/4.1 < (61.25 - 55.4)/4.1)
… ≈ P(<em>Z</em> ≤ 0.1427)
… ≈ 0.5567
(B)
P(<em>X</em> > 46.5) = P((<em>X</em> - 55.4)/4.1 > (46.5 - 55.4)/4.1)
… ≈ P(<em>Z</em> > -2.1707)
… ≈ 1 - P(<em>Z</em> ≤ -2.1707)
… ≈ 0.9850