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歡迎您訪問數(shù)學考題練習:商店出售下列形狀的地磚:①正方形;②長方形;③!

數(shù)學考題練習:商店出售下列形狀的地磚:①正方形;②長方形;③

更新時間:2024-01-12 16:27:02作者:貝語網(wǎng)校

商店出售下列形狀的地磚:①正方形;②長方形;③三角形;④正五邊形;⑤正六邊形;⑥正八邊形.若只選其中一種地磚鑲嵌地面,可選擇的地磚共有

A.3種

B.4種

C.5種

D.6種

試題答案

B

試題解析

由鑲嵌的條件知,在一個頂點處各個內(nèi)角和為360°.

解答:①正方形的每個內(nèi)角是90°,4個能組成鑲嵌;

②長方形的每個內(nèi)角是90°,4個能組成鑲嵌;

③任意三角形的內(nèi)角和是180°,放在同一頂點處6個即能組成鑲嵌;

④正五邊形每個內(nèi)角是180°-360°÷5=108°,不能整除360°,不能密鋪;

⑤正六邊形的每個內(nèi)角是120°,能整除360°,3個能組成鑲嵌;

⑥正八邊形的每個內(nèi)角為:180°-360°÷8=135°,不能整除360°,不能密鋪.

故選B.

點評:本題考查一種正多邊形的鑲嵌應符合一個內(nèi)角度數(shù)能整除360°.任意多邊形能進行鑲嵌,說明它的內(nèi)角和應能整除360°.

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