ex.5 si 6..............

Răspuns:
5) 180-73=107 grade unghiul 2
6) a=2/3b
a+2/3b=180
2/3b+b
2b+3b=180x3=540
5b=540
b=108
a=2/3 x 108
a=2x36
a=72
108+72=180