\begin{array}{c}\color{#003366}{Sp}\color{#005A9C}{ron}\color{#007ACC}{kBo}\color{#00AEEF}{b}\color{#00CFFF}{bb}\color{#A4D3EE}{}\color{#D3D3D3}{}\color{#E0E0E0}{}\end{array} 

`***` Các cặp góc bằng nhau là

`@ hat{A3} = hat{B3}` (`2` góc đồng vị)

`@ hat{A2} = hat{B2}`(`2` góc đồng vị)

`@ hat{A4} = hat{B4}`(`2` góc đồng vị)

`@ hat{A1} = hat{B1}` (`2` góc đồng vị)

`@ hat{A1} = hat{B3}` (`2` góc so le trong)

`@ hat{A4} = hat{B2}` (`2` góc so le trong)