1) P = 2(100 + 90) + π x D = 380 + π x 90 = 380 + 3.14 x 90 = 662.5 cm
P = 663 cm
2) A = 1/2 x BG x GH = 1/2) x 30 x 21.63 = 324.45 cm²
BG² = GC² + BC² = 18² + 24² = 324 + 576 = 900 ⇒ BG = √900 = 30 cm
GH² = DG² + HD² = 18² + 12² = 324 + 144 = 468 ⇒ GH = √468 = 21.63 cm
3) la figure n'est lisible et tronquée