按图填空, 并注明理由已知: 如图, ∠1=∠2, ∠3=∠E. 求证: AD∥BE
![](http://tikupic.21cnjy.com/dd/1c/dd1ca4a59117cd08cab36a345e7ddf16.png)
证明: ∵∠1 = ∠2 (已知)
∴ {#blank#}1{#/blank#}∥{#blank#}2{#/blank#}( {#blank#}3{#/blank#})
∴ ∠E = ∠{#blank#}4{#/blank#}({#blank#}5{#/blank#})
又∵ ∠E = ∠3 ( 已知 )
∴ ∠3 = ∠{#blank#}6{#/blank#} ( 等量代换 )
∴{#blank#}7{#/blank#}∥{#blank#}8{#/blank#} ( 内错角相等,两直线平行 )