Զուգահեռագիծ
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-66.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-67.png)
<CAB=180-70-60=50
AC=AC, <ACD=50, CD=BA, <CAB=50 => եռ.BAC = եռ.CAD(1-ին հայտանիշ) => BC = AD
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-68.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-69.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-77.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-79.png)
BC=15+9=24
AD=24
<KAD=<AKB(խաչադիր)=>AB=BK=15
AB=15
CD=15
AD=24
BC=24
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-70.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-72.png)
<DOC = <ADO(խաչադիր անկյուններ) => եռ.OCD(հավասարասրուն)
OC=DC=14
DC=14
AB=14
BC, AD=21
21*2+14*2=70սմ
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-74.png)
![](https://koryun.gaboyan.am/wp-content/uploads/2022/09/image-75.png)