在一次研究性学习活动中，李平同学看到了工人师傅在木板上画一个直角三角形，方法是（如图）：画线段AB，分别以点A，B为圆心，以大于AB的长为半径画弧，两弧相交于点C，连接AC；-九年级数学

更多内容推荐

• 长为12cm的铁丝，围成边长为连续整数的直角三角形，则斜边上的中线为（）cm。-九年级数学
• 阅读理解。 "Just five more minutes." "I'm tired!" "I can't get up.&quo
• 阅读理解。 "Old wives tales" are beliefs lasting for many generations. For example, most of us
• 阅读理解。 The gray-haired lady can't wait to leave the building to search for her dad. Unless watch
• 若一个三角形的三边a、b、c满足a2+b2+c2=10a+24b+26c-338，则这个三角形一定是[]A、直角三角形B、锐角三角形C、等腰三角形D、等腰直角三角形-八年级数学
• 阅读理解。 In the past industries had more freedom than they have now, and they did not need to be as car
• 阅读理解。 Africa is home to nearly 700 lakes and rivers. It holds the largest amount of water on earth.
• 阅读理解。 Living in a green area can make you live longer, according to research published today. The re
• 直角三角形ABC中，∠ACB=90°，CD是AB边上的高，AB=5cm，CB=4cm，AC=3cm，求：（1）△ABC的面积；（2）CD的长。-七年级数学
• 如图，在Rt△ABC中，CD是AB斜边上的中线，如果CD=2cm，那么AB=（）cm。-八年级数学
• 如图，在Rt△ABC中，∠C=90°，∠1=120°，如果BC=1，则AB=（）。-九年级数学
• 如图，Rt△ABC中，∠ACB=90°，CD⊥AB于D，∠ACD=40°，则∠B=（）。-七年级数学
• 阅读理解。 Running, as most of you already know, is a sport that all sorts of people love. Running a mara
• 阅读理解。 On a rainy day, you will see many streams of muddy (多泥的) water running down the slopes (山坡) of
• 阅读理解。Dear Editor (编辑),I used to be a doctor in a children's hospital. Sometimes I treated child
• 阅读下列材料，从所给的六个选项(A、B、C、D、E和F)中，选出符合各小段的最佳的标题选项。选项中有一项是多余选项。 A. Illegal hunting has caused a decrease
• 阅读理解。 An allergy (过敏反应) is a strong reaction to a substance. Many things can cause allergies. The mo
• 阅读理解。 A picture, a calendar or even a balloon may be the best way for millions of people living in C
• 阅读理解。 Jim suffered heart problems. In conversation he expressed little joy and it seemed that his li
• 阅读理解。 This is not a diet. It's a simple way to lose weight And you don't even have to give
• 阅读理解。 Can you imagine that you can save your own life during a heart attack (心脏病发作) by coughing (咳嗽)
• 阅读理解。 No air means death. Although we can't see it, there is air around us. So air is everythin
• 阅读理解。 It's you and I who are to blame for the state of the earth. No question about it. It'
• 如图，点P是∠AOB的角平分线上一点，过P作PC//OA交OB于点C，若∠AOB=60°，OC=4，求点P到OA的距离PD。-九年级数学
• 直角三角形三边长分别为6，8，10，那么它最短边上的高为[]A.6B.4.5C.2.4D.8-七年级数学
• 如图，∠ACB=90°，CD⊥AB，则∠1与∠B的关系是[]A.互余B.互补C.相等D.不确定-七年级数学
• 已知：∠α，∠β=90°，线段a。求作：Rt△ABC，∠B=∠α，∠C=∠β，BC=2a。（不写作法，保留作图痕迹，下结论）-七年级数学
• 清朝康熙皇帝是我国历史上一位对数学很有兴趣的帝王，前不久，在西安发现了他的数学专著，其中有一文《积求勾股法》，它对“三边长为3、4、5的整数倍的直角三角形，已知面积求边-八年级数学
• 阅读理解。 Jim suffered heart problems. In conversation he expressed little joy and it seemed that his li
• 阅读下面短文，并根据短文后的要求答题。 Walking is a popular form of exercise. It is an easy activity and offers a good
• 阅读理解。 Early rising is helpful in more than one way. First, it helps us to have good health. We all n
• 阅读理解。 The island nation of Tuvalu (图瓦卢) in the Pacific Ocean wants the bigger countries of the world
• 直角三角形两锐角的平分线所交的角的度数是[]A.45°B.135°C.45°或135°D.以上答案都不对-七年级数学
• 如图，已知在Rt△ABC中，∠ACB=90°，AC=3，BC=4，点P是斜边AB上（不与A、B重合），过P作PE⊥AC，PF⊥BC，垂足分别是E、F，连结EF。随着P点在边AB上位置的改变，EF的长度
• 某楼梯的侧面视图如图所示，其中AB=6.5米，BC=2.5米，∠C=90°，楼梯的宽度为6米，因某种活动要求铺设红色地毯，则在AB段楼梯所铺地毯的面积应为（）。-七年级数学
• 如图，已知△ABC中，D是BC的中点，DE∥AB交AC于E，BF平分∠ABC，交DE于点F。（1）若BC=2，求DF的长；（2）连结FC，求∠BFC的度数。-八年级数学
• 如果三角形的一个角等于其它两个角的差，则这个三角形是（）三角形。-七年级数学
• 阅读理解。 Almost 40 years ago, a community service organization started providing eye care in Gujarat St
• 阅读理解。 The United States has about 475,000 school buses-all painted yellow. Each day they carry more
• 已知a、b、c为三个正整数，如果a+b+c=12，那么以a、b、c为边能组成的三角形是：①等腰三角形；②等边三角形；③直角三角形；④钝角三角形，以上符合条件的正确结论是（）。（只填序号-八年级数学
• 阅读理解。 The medical world is gradually realizing that the quality of the environment in hospitals may
• 阅读理解。 Would you eat a ready meal from the fridge rather than cook from scratch? Have you been doing
• 阅读理解。 It's not always easy to eat healthy foods when others seem to eat whatever they want. Fol
• 直角三角形两直角边的长分别是3和4，则它斜边上的高是[]A.3.5B.2.4C.1.2D.5-八年级数学
• 阅读理解。 Do you love holidays but hate the increase weight that follow? You are not alone.Holidays are
• 阅读理解。On AngerDoctors say anger can be an extremely harmful emotion, unless you learn how to deal wit
• 阅读理解。 The physicians in a hospital form the center of medical staff. But they could not provide effe
• 阅读理解。 While students in Hainan are quite used to clear skies, Beijing teenagers are not so lucky. As
• 根据课文内容用适当的词填空，使短文完整。(一空一词) Not long ago, a girl called Daisy took a magic 1.______ around the world
• 直角三角形的两个锐角平分线所夹的锐角是[]A.30°B.60°C.45°D.15°和75°-七年级数学