m(unghiB)=2·m(unghiuluiA)
m(B)=2·25grade=50grade
masura unghiurilor intr-un tringhi este de 180grade
m(A)+m(B)+m(C)=180grade
25grade+50grade+m(C)=180grade
75grade+m(C)=180grade
m(C)=180grade-75grade=105grade
m(unghiuluiC)=105 grade
Sper ca te-am ajutat.:>:))))