f two simir triangles?“
“yes,“ replied herbert;“their homologous sides are proportional.“
“well, my boy, i have just constructed two simir right-angled triangles; the first, the smallest, has for its sides the perpendicur pole, the distance which separates the little stick from the foot of the pole and my visual ray for hypothenuse; the second has for its sides the perpendicur cliff, the height of which we wish to measure, the distance which separates the little stick from the bottom of the cliff, and my visual ray also forms its hypothenuse, which proves to be prolongation of that of the first triangle.“
“ah, captain, i understand!“ cried herbert.“as the distance from the stick to the pole is to the distance from the stick to the base of the cliff, so is the height of the pole to the height of the cliff.“
他们利用木杆量出了两段水平距离,木杆在沙滩上的高度是十英尺整。第一段距离是从小棍子到插木杆的地方,相距十五英尺。第二段距离是从小棍子到峭壁底部,相距五百英尺。
15:500=10:x
500x10=5000
600015=333.3
由此得出,花岗石峭壁的高度是三百三十三英尺。
the two horizontal distances were found out by means of the pole, whose length above the sand was exactly ten feet.
the first distance was fifteen feet between the stick and the pce where the pole was thrust into the sand.
the second distance between the stick and the bottom of the cliff was five hundred feet. from which it was proved that the granite cliff measured 333 feet in height.
圆规两脚之间的距离就是十字架二和水平线之间的角距。他首先把一个圆周分成三百六十等分,然后非常精确地把圆规角度落在圆周上,得出的结果是10度
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