delta公式

甲乙两艘军舰,从两个港口相向开出,甲舰每小 时行42千米,乙舰每小时行38千米,乙舰 开出一小时后,甲舰才开出,再经过4小时 两舰相遇.两个港口相距多少千米? x²-12x+35=0 因式分解法 ｛2x-3y=-5,3x+2y=12.二元一次方程,用代入消元法做! 三（1）班同学为庆祝六一儿童节排成方阵排练节目,李小杰的东西南北四个方向各有3名同学,这个班一共有多少名同学? The ___(many) trees and flowers we plant,the more beautiful our school will be. Our school is very quiet and beautiful___by many trees and flowers.Why use 'surrounded'? Our school has many flowers.（同义句）______ ________ many flowers ______our school 求值：sin10兀/3-√2cos(-19兀/4)+tan(-13兀/3) -sin兀/3是多少 化简丌sin(－a）sin(2兀－a）sin(3兀＋a）÷sin（a－兀）sin(3兀－a）sin(a＋兀）化简后的丌不是本题的，应该是: 丽丽在计算3 a时,误把3 a当作3a来计算,结果为27,正确答案是多少?列式计算 丽丽在计算3+a,误把3+a当作3a来计筸,结果为27,正确的答案是多少? 王超在计算3+a时,误把3+a当作3a来计算,结果为27,正确结果是多少? 小明在计算a+3时,误把a+|3看作3a来计算,结果为27,正确结果是多少? 丽丽计算一个数除以5分之3时,看成乘5分之3,结果是55分之27,正确结果是几 （）this place is usually very big.There are many trees,grass and flowers in it.People often填什么接：take exercise in the morning or take a walk in the afternoon there.Maybe there are some lakes in it. there are many trees in this place.树作宾语,还是地方作宾语 it is a beautiful place.There are many ancient buildings in it.(合并为一句）it is a beautiful place ___ _____ ancient buildings. It's a beautiful place,but there are so many people there that I couldn't 为but there are so many people there that I couldn't find a proper place to take photos.为何用but,不用so? 麻烦,填空.1.Welcome to our school.Let me( )you around.2.Look,this is our( )pool. w--- to our school ,is this your bag?根据首字母提示完成句子 求This is our school小学五年级水平的英语作文至少50词! 不要太简单最好20道题 （a+b+c）（a+b- c）=[（ ）+（ ）][（ ）- （ ）]（a- b+c）（a+b- c）=[（ ）+（ ）][（ ）- （ ）]（a+b+c）（a- b- c）=[（ ）+（ ）][（ ）- （ ）] 27分之10 x18x5分之3 13分之11x11分之26＋13分之2 6分之5x15分之8×4分之3 13分之7x4＋13分之6x4(18分之7＋9分之5）x35分之27 99x100分之1 我的学校 My School My school is very beautiful. It is in Guicheng, near the Qiandeng Lake. Do you 翻译一下我的学校 My School My school is very beautiful. It is in Guicheng, near th 用简算计算0.86+9.9x8. 两个数相除商4余8,已知被除数比除数大59,求被除数 方程 两个数相除,商5余4,已知被除数40,除数是多少?列方程 Was Thomas Edison an American inventor?这句疑问句对吗? (My)school is very beautiful(就打括号部分提问） My school is___(real) beautiful.