Respuesta :

chudung1976
You can revise: the sum of the two adjacent angles is 180°
and the sum of the measurements of the three corners in a triangle is also 180°
<1= 180°-57°=123°
As <2=52°, so we have <3= 180°-(28°+71°+52°)= 180°-151°=29°
have fun