Question

Cho tứ giác BCDE có B=50°,C=90°,E=100°.Tính số đo góc D

Answer 1

D= 360o-(50o+90o+100o)=110o

Answer 2

Ta có: \(\widehat{B}+\widehat{C}+\widehat{E}+\widehat{D}=360^0\)

\(50^0+90^0+100^0+\widehat{D}=360^0\)

\(240^0+\widehat{D}=360^0\)

\(\widehat{D}=360^0-240^0\)

\(\widehat{D}=120^0\)

Vậy \(\widehat{D}=120^0\)