Răspuns:
75Grade
Explicație pas cu pas:
Ipoteza: ΔABC Isoscel
∡ACD exterior
m(∡ACD) = 150Grade
Concluzie: m(∡BAC) = ? Grade
Demonstratie:
m(∡ACD) = 150 Grade
m(∡ACB) = 180 Grade - 150 Grade
m(∡ACB) = 30 Grade
m(∡BAC) = ?
m(∡ABC) + m(∡BAC) = 180 Grade - 30 Grade
m(∡ABC) + m(∡BAC) = 150 Grade
m(∡ABC) = m(∡BAC) = 150 Grade
m(∡ABC) = 150 Grade : 2
m(∡ABC) = 75 Grade
m(∡BAC) = 150 Grade : 2
m(∡BAC) = 75 Grade