证明:过A,D作AM⊥BC,DN⊥BC分别交BC于M,N,
∵AD∥BC,
∴AM=DN,
∵AC=BD,
∴△AMC≌△DNB,
∴BN=CM,
∴BM=NC,
∵AM=DN,AM⊥BC,DN⊥BC,
∴△ABM≌△DCN,
∴AB=DC,
∴梯形ABCD是等腰梯形.
猜你喜欢
- 1在盒中有10个相同的球,分别标有号码1.2.3.10,从中任取一个球,则此球的号码为偶数的概率是?
- 2过动点P(x,y)引圆(x-1)^2+(y-2)^2=1的切线,其切线长等于点P到原点O的距离
- 3将一个长方体平均截成4段,每段长5分米,表面积增加了324平方分米.求原长方体的体积.
- 4一个分数,如果分母加上11,分数值等于1/2,若分母乘以2,分子减去13,则分数值等于1/10,求原数.
- 5I don’t know __.A.what to say or do B.what to say and to do C.how to say and to do
- 6they played football last weekend.改为一般疑问和否定句.
- 7已知tanα=2,求2sin² α - 3sinαcosα的值
- 8Would you like to go shopping with me this afternoon?请问这句英语有没有错.
- 9FIXTURE NOTE THIS WILL CONFIRM THE FREIGHT CONTRACT MADE BETWEEN CHARTERERS AND OWNERS ON THE FOLLO
- 10量筒读数时,仰视和俯视有什么缺点