In trapez baza mare este AB, iar baza mica este DC. Construiesti inaltimile DM si CN
DC//MN
DC=5cm⇒MN=5 cm
AM=NB=(17-5):2=12:2=6 cm
In Δ DMA, m M=90
AM=6 cm
AD=10 cm⇒Th Pitagora DM²=AD²-AM²
DM=√64=8 cm
sin A=[tex] \frac{DM}{AD}= \frac{8}{10} = \frac{4}{5} [/tex]
tgA=[tex] \frac{DM}{AM} = \frac{8}{6} = \frac{4}{3} [/tex]
