bonjour
1. Aire = ( 3 + x ) ( 10 + x ) = 30 + 3 x + 10 x + x² = x² + 13 x + 30
2. par codage , forme carrée
3 aire jardin = x² + 13 x + 30 - x² = 13 x +30
4. aire terrain = 81 + 13 *9 + 30 = 228 m²
airejardin = 9 * 13 30 = 147 m²
13 x + 30 = 88.5
13 x = 88.5 - 30
13 x = 58.5
x = 4.5
