如图,在一块长为22米,宽为17米的矩形地面上,要修建同样宽的两条互相垂直的道路(两条道路各与矩形的一条边平行),剩余部分种上草坪,使草坪面积为300平方米,那么道路的宽度应该是多少?
解:设道路的宽应为x米,由题意有
(22﹣x)(17﹣x)=300,
解得:x1=37(舍去),x2=2.
答:修建的路宽为2米.
他是我的爸爸。
设游戏者从圈A起跳.
根据句意,用括号中所给单词的正确形式填空。①The new students had always lived with their parents before they came here. They are not used to____ (be) away from home.②Antonio is liked by everyone because he is always ready ____ (help) others.③Teenagers should ____ (allow) to go out with their friends.④We hope the weather will be fine, but it is getting even____ (bad).⑤He believed his lucky number was 12, so he decided to live on the ____ (twelve) floor.⑥Timmy has spelt the name____ (correct). That’s why his friend can’t find him easily.⑦I wonder if there are any____ (suggest) about how to learn English well.
溶液在生产和科研中具有广泛的用途,与人们的生活密不可分.
(1)衣服沾有的油污,可用汽油洗去,是因为汽油能____(填“溶解”或“乳化”)油污.
(2)喝了冰镇汽水以后,常常会打嗝,这种现象说明气体的溶解度与____有关.