bonjour
2 a + 2 b = 161 ⇔ a + b = 80.5
ab = 1 431
a = 80.5 - b
( 80.5 - b ) b = 1 431
- b² + 80.5 b - 1 431 = 0
Δ = 6 480.25 - 4 ( - 1 * - 1431 ) = 6 480.25 - 5 724 = 756.25 = 27.5 ²
x 1 = ( - 80.5 - 27.5) / - 2 = 54
x 2 = ( - 80.5 + 27.5 ) / - 2 = 26.5
la piscine mesure 54 m sur 26.5 m
