题干

如图:矩形ABCD的长AB=30,宽BC=20.

(1)如图(1)若沿矩形ABCD四周有宽为1的环形区域,图中所形成的两个矩形ABCD与A′B′C′D′相似吗?请说明理由;

(2)如图(2),x为多少时,图中的两个矩形ABCD与A′B′C′D′相似?

上一题 下一题 0.0难度 选择题 更新时间:2019-07-06 10:58:42

答案(点此获取答案解析)

解:(1)不相似,
AB=30,A′B′=28,BC=20,B′C′=18,
2830
1820
(2)矩形

同类题3

阅读下文,回答下列问题。
                                                                                               永远的小女儿
                                                                                                   刘墉
  母亲节快到了,小敏“照例”要送妈妈一张贺卡。
  小敏特别到店里,挑了一张国外进口的卡片。表面是锦缎的花朵,四周烫着金边,角上还系了一个粉红色的蝴蝶结。唯一可惜的是,里面只印了一首英文小诗,所幸小敏的英文好,虽有两个字看不懂,查查字典也就了解。
  “亲爱的妈妈!/你是我的怀抱、我的亲吻。/你是我的花园、我的港湾。/你是我幻想的实现者、梦想的催生者。/你更是/我心灵的家!”
  小敏买回来,读了一遍又一遍,觉得这设计卡片的人,真是自己的知音:“他写出了我要说的话!”
  小敏在上面用中文写上了“妈妈”,又在下面签了自己的名字,早晨出门前,把卡片留在餐桌上。
  “妈妈看到这么漂亮的卡片,一定会好高兴!”小敏心想:“这是我长到十八岁以来,送的最贵的一张了!”
  果然,进门时,看到妈妈一张笑脸,从厨房探出来。
  “你喜欢我送的卡片吗?好贵吔!”小敏得意地说。
  “当然喜欢啦!”妈妈拿着一个盒子走出来:“我把这张卡片跟你以前送的摆在一块。”
  妈妈打开盒子,把卡片一张张放在桌上。居然从小到大,小敏送的十几张卡片,妈妈全像宝贝一样藏着。
  “看!这是你在幼稚园画的。还不会写字,由老师帮你写‘亲爱的妈妈’!”
  “这一张会写妈妈了,歪歪扭扭的,大概是小学一年级吧!”
  “这张写得就更好?,还会写‘妈妈我好爱你,你是我的大太阳’,多可爱啊!”妈妈笑得好开心。
  又拿出一张。
  “这张是小学六年级,画得精致,字也漂亮,里面的信更感人。”妈妈抬起头:“你知道吗?看这张卡片,我流了好多眼泪,看了一遍又一遍,直到今天,还是好感动!”
  再拿出一张,已经是存钱买的,只是印刷不够好,卡片上的颜色都套不准。里面“母亲节快乐”几个字,也印得很粗拙。所幸,小敏另外写了一首短诗。
  接下来的两张,印得已经比较好了,文字也设计得不错。配上小敏写的几句感谢的话,还蛮耐看的!
  “至于去年这一张,是印得更美了。”妈妈叹口气:“只是大概因为你功课忙,没写什么字。也可能是人家设计的文字已经很好,所以只需要填个名字。”
  终于打开今年的信封,抽出那张华丽的锦缎卡片,妈妈笑着翻过来、翻过去:“怪妈不懂英文,不知道上面的意思。你说给妈听听吧!”
  “不!”小敏居然抢过卡片:“这张卡片不好!我要换一张。”说完就跑进自己房间
  小敏画了一张大大的母亲节卡。上面写着:
  “亲爱的妈妈,看到以前我送您的卡片,才发觉自己长得愈大、读的书愈多、却也愈跟您疏远。我以为可以用物质、金钱表示我的爱。但是今天,我发觉自己错了。您真正在乎的,是我,您的女儿。让我做您永远的小女儿,像小学、像幼稚园时一样,那么真实、那么贴心、那么爱……”
  当我们年龄渐长,愈来愈觉得钱之可贵,就可能用钱去衡量一切,甚至       。岂知在这世界上,没有钱之前,早       。当我们没有赚到钱之前,早        
  我们因爱而来到人世,有一天离开,带不走钱,只带得去满怀的爱。

同类题4

阅读理解

    When people find something valuable and return it to its owner,they are often given a reward.This is because the person not only found what was lost but also spent time finding its owner or taking it to the police station.

    There was once a young boy who found a woman's purse in a shopping center.Inside the purse there was some money and the woman's driving license.Her name and address were printed on the license,so the boy knew where she lived.That evening he went to her house and knocked on her door.When she opened it,he said,“I found your purse,''and handed it to her.

    “Thank you very much,”she said.She opened her purse and took out all the money.She wanted to give the boy a small reward,but there were only bills of$20 in the purse and she thought that$20 was too much to give the boy.“I'm sorry,”she said. “but I don't have any small change to give you.”

    The boy said,“That's all right,”and he went away.

    A few days later he found another woman's purse.It also had her driving license in it,so he knew where she lived.He went to her house and said.“l found your purse ,”and handed it to her.

    “Thank you very much,"she said.  She opened her purse and took out all her money.

    “That‘s strange,”she said.“Before I lost my purse l had a $100 bill and a $20 bill in it.Now I have a $100 bill ,a $10 bill and two $5 bills.''

    “Yes,"the boy said,and smiled.