Question

Fie DEFG un romb.Daca (<GDF)=31grade,aflati m(<DEG).

Answer 1

DEFG romb⇒DE≡DG≡EF≡FG
in ΔDEG, DE≡DG⇒ΔDEG isoscel⇒∡DEG≡∡DGE
in ΔDEG suma ∡ = 180°, deci
∡DEG+∡DGE+∡EDG=180°
2∡DEG+31°=180° deoarece (∡DEG≡∡DGE)
2∡DEG=180-31
2∡DEG=149°
∡DEG=74,5°