Question

ABCD tr AB||CD AB=12 CD=18 C=30° D=60° AD se intersecteaza cu BC in M P,A=?

Answer 1

MDC este un triunghi, dar m(M)=180-30-60=90=>MDC dreptunghic
DM=1/2DC=9 (T30)
Aplic TP in MDC=>MC=9radical din 3
AB//DC=> MAB~MDC=>AB/CD=MA/MD=>MA=6
Se observa ca MA=1/2AB=>m(MBA0=30=>m(MAB)=60
m(DAM)=180
m(DAB)=180-60=120=>A=120