S5 Math
2013-09-21 8:15 pm
A piece of wire which is 40 cm long is cut into two pieces. The two pieces are bent to form a square and a circle of the same area respectively. Find the length of a side of the square and the radius of the circle. (corr to 3 sign. fig.)
回答 (2)
2013-09-21 8:54 pm
✔ 最佳答案
Let x cm be the length of the square.Let r cm be the radius of the circle.
x² = 兀r²
x = (√兀)r
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4x + 2兀r = 40
4r(√兀) + 2兀r = 40
r(4(√兀) + 2兀) = 40
r = (40) ÷ (4(√兀) + 2兀)
r = 2.99 (to 3 sig.fig)
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x = (√兀)r
x = (√兀)((40) ÷ (4(√兀) + 2兀))
x = 5.30 (to 3 sig.fig)
參考: 自己 + 計算機
2013-09-21 9:28 pm
The length of a side of the square is 5.30 cm.
the radius of the circle is 2.99 cm.
the radius of the circle is 2.99 cm.
收錄日期: 2021-04-18 14:15:30
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20130921000051KK00069