Step-by-step explanation:
m/1 = ( 180 - 65 - 46 ) - 180
= 180 - 59 = 121
m/2 = 180 - 121 = 59
m/3 = ( 180 - 142 ) - 180
= 180 - 32 - 82
= 66
m/4 = 66
m/5 = 180 - m/2 - m/4
= 180 - 59 - 66
= 180 - 125 = 55
The sum of interior angles of triangles = 180°
