Réponse :
1) P1 = 2(1.5 x + x) = 5 x
S1 = 1.5 x * x = 1.5 x²
2) P2 = 2( 1.5 x + 2 + x + 2) = 2(2.5 x + 4) = 5 x + 8
S2 = (1.5 x + 2)(x + 2) = 1.5 x² + 3 x + 2 x + 4
= 1.5 x² + 5 x + 4
3) AC² = (1.5 x)² + x² = 3.25 x² ⇒ AC = x√(3.25)
EG² = (1.5 x + 2)² + (x + 2)² = 2.25 x² + 6 x + 4 + x² + 4 x + 4
= 3.25 x² + 10 x + 8
4) S2 = 1.5 (10)² + 5 (10) + 4 = 150 + 54 = 204 cm²
AC = 10√3.25 cm ≈ 18 cm
EG² = 3.25 (10)² + 10 (10) + 8 = 325 + 100 + 8 = 433 ⇒ EG = √433 = 20.8 cm
Explications étape par étape
