un rad=180*/π
suma masurilor unghiurilor unui poligon este (n-2).180*
a) α=60
180............................π
60..............................x formula de transformare
x=π/3
b) α=90 ⇔α=π/2
c) α=108 ⇔α=3π/5
d)α=120 ⇔α=2π/3
e)α128,57 ⇔α=5π/7
f)α=135 ⇔α=3π/4
g)α=145⇔α=145π/180=29π/36
h)α=150 ⇔α=5π/6
