Question

ajutorrrr

In paralelogramul ABCD, m(ABC)=120°,AB=8 cm AD=10cm Calculati perimetrul si aria.

Answer 1

∡DAC + ∡ABC = 180° (suplementare) =>

∡DAC = 180° - 120° = 60°

A(ABCD) = AB×AD×sinDAC

= 8×10×sin60°

= 80×√3/2

= 40√3 cm²

P = 2AB + 2AD

= 2×8 + 2×10

= 16 + 20

= 36 cm